House: Interesting reflex of guilt just now. Your patient's been dying for six weeks. Couldn't have predicted he'd go this weekend. Or could you? 'Euthanasia. Let's tell the truth, we all do it.' It's a great opening line. Are you insane?!

Wilson: I didn't want your notes before, and I don't want them now.

— Known Unknowns

Known Unknowns is a 6th season episode of House which first aired on November 9, 2009. After a wild night out, a teenage girl (guest star Annabelle Attanasio) is brought to Princeton-Plainsboro Teaching Hospital with severely swollen appendages. The team must work to diagnose the young girl, who is less than honest about what happened the night she fell ill. As her condition worsens, she becomes unable to distinguish fact from fiction and she starts to lose blood faster than the team can transfuse. Meanwhile, Wilson, Cuddy, and House spend a weekend away from the hospital to attend a medical conference, but things don't go as planned when House's private investigator, Lucas Douglas, returns. House confesses his feelings for Cuddy to Wilson who says that she is better off without House. Chase's strange behavior after the death of Dibala leads Cameron to believe that Chase is having an affair.

This episode provides a linchpin in the story arcs of Huddy and the relationship between Cameron and Chase. House appears to be ready to admit to both himself and Cuddy that not only is he interested in her, he has always been interested in her. Meanwhile, Cameron is sure her marriage to Chase is coming to a rapid end. She turns out to be right, but not for the reason she thought. Although neither story arc is resolved in this episode, the events of future episodes depend on the events in this one.

The theme of the episode, wrapped up in the title, is secrets and knowledge. In both the medical mystery and the soap opera, almost every character is hiding something, and every character has something revealed to them. For once, it appears that the only person who isn't interested in pursuing a policy of obfuscation is House himself. As his dreams come crashing down around him, he still has to find time to stop the self-destructive impulses of both the patient and Wilson.

It's nice to see the tables turned in this episode as Wilson takes the dangerous course and it's House who is put in the role of the possible enabler. In Role Model, House is given the chance to redeem himself in public at Wilson's urging, but Wilson turns to enabling House once again, nearly costing himself his career in the process. In Seasons 1 and 3, House was completely uninterested in how his pursuit of his own moral imperative was affecting Wilson's career; but now that the tables are turned, House can seemingly think of nothing else but to save Wilson from himself.

On the patient's side, Jordan's lies are balanced by her BFF Phoebe, who, when she can, corrects her friend's unreliable narration of the previous night's events. But when Phoebe finds herself unable to fill in the blanks, Cameron is more than willing to write her own narrative. However, Cameron's narrative is driven less by her native distrust of a comic book artist but more by projecting her belief that Chase is deep into an affair onto the artist.

In the end, it's Lucas Douglas, the master detective, who appears to have the right philosophy. He knew the truth would come out eventually and he couldn't understand Cuddy's reluctance to let House in on their relationship. He also turns out to be right about House being able to handle the reality of the situation. He, better than anyone, knows finding the truth is often just a matter of hard work, observation, and leaving one's preconceived notions of the truth behind.

While a young woman recalls her night with a rock band, her friends notice that her left ankle has swollen up. She suddenly notices her hands have swollen up too, and she collapses on the carpet.

House is complaining that Foreman has e-mailed him an X-ray that he can't read on his cell phone screen. Wilson reminds House that they are going to a medical conference that afternoon, but House doesn't want to go. Wilson reminds him that as a term of his release from Mayfield Psychiatric Hospital, they have to stay together. House tells him that he will tell Foreman he can't deal with the new patient, but he's not going anyway.

House arrives at the hospital where the team explains the patient has severe edema, seemingly because she has the joints of a much older woman. House figures she just has Rhabdo from trauma; she said she jumped off a fence into a pool. The rest of the team have other theories, but House insists. Chase agrees to perform the tests for all the suggested diagnoses.

Chase confides in Foreman that Cameron thinks he's cheating on her.

House goes to get Cuddy to agree to release the patient, and realizes she's going to the medical conference too. He says he's going as well but she's checked and his name isn't on the list of attendees.

House goes to Wilson to tell him he's going to the conference. Wilson realizes House knows Cuddy is going, and tells him to be ready in two hours.

Chase comes in and tells him he can't leave and that the patient can't have Rhabdo because there is no sign of muscle crush. However, House goes to give the patient a pair of drumsticks and asks her to play along. She does for a while, but soon becomes unable to move her arms. He realizes her potassium was too low the previous night to climb stairs to jump into the pool or to play the drums with the band and tells Chase to get a better medical history and that the patient is a liar who still has Rhabdo.

They question the patient and she admits that instead of staying with the rock band, they followed a comic book artist around for several hours, including following him to a restaurant. Cameron goes to get food from the restaurant, but they note no-one else got sick. Foreman realizes that she ate the whole meal despite being thin. He figures the patient might be bulimic. They go to do a barium swallow.

Wilson and House go to pick up Cuddy. House finds out Wilson is presenting at the conference, but wonders why he didn't ask for feedback like he usually does. Wilson tells House to ask Cuddy out, but House has a plan. Cuddy shows up with Rachel.

Cameron asks Foreman about Chase. He tells her to talk to Chase and that Chase is not having an affair. The barium swallow is negative and bulimia is ruled out. However, when the patient's parents show up, she starts to crash. They realize she is bleeding into her heart.

They call House, who figures it might be a toxin. Cameron goes to do an environmental scan and House says get a better medical history.

House is masquerading as a "Dr. Phil Perlmutter" to get into the conference.

Foreman questions the patient and her friend, and they soon realize that the patient is making things up. He then notices she is bleeding out of her ear.

Cameron catches up with the comic book artist. He remembers the patient and her friend, and makes a pass at Cameron.

Foreman realizes that she is also bleeding into her brain, which has affected her thalamus and her memory. He also finds out that there was a gap when the patient went to "get ice" that the friend can't account for.

House and Cuddy meet at a 1980s-themed costume party, House dresses jokingly in 1780's fashion with a coat, ruffles and wig. They start dancing and recollect about how they first met. It was Cuddy's third day at school. She was at the bookstore and House figured her out in about thirty seconds. They talk about who approached whom, and how they tracked each other down at a party. House said he was going to call Cuddy, but that was the day he found out he had been expelled from Hopkins and saw no point in pursuing anything. Cuddy, seemingly surprised and flustered by the revelation, leaves to go back to her room.

Wilson gets a call telling him his patient has passed away. House said he told Cuddy he was always interested in her, and she just walked out. House finds out that Wilson's talk is about euthanasia.

Chase and Cameron try to track the patient's movements on security cameras. They realized she went back for a journal that the comic book artist left behind in the restaurant so she would have an excuse to meet him.

Wilson and House go down to the lake to discuss his paper, and House tells him not to say it openly - it will ruin his career. Wilson says he has to say what he thinks is right, just like House would. House reminds him that hasn't worked out for him personally.

Cameron and Chase go to see the comic book artist and confront him and ask to search the room. He shuts them out. Chase tells Cameron the artist would never risk his wife and career for a one-night stand, and follows up that he isn't having an affair either. Cameron doesn't believe the artist and realizes the patient's symptoms are explained by an overdose of roofies.

Wilson goes to see Cuddy and Rachel. They talk about House. She says she can't rely on him, especially now that she's a mother.

Foreman rejects Cameron's diagnosis because the patient is now bleeding behind her kidneys. Foreman is transfusing red blood cells, but the patient keeps bleeding out. Cameron thinks it is a toxic reaction and suggests using amobarbital as a truth serum. Chase accuses her of being angry at the comic book artist and taking it out on him. Chase want to call House, but Foreman says House wouldn't go with anything safer.

House is dipping into the minibar despite the buffet downstairs. They talk about Wilson's speech again. Wilson deflects and tells him to go see Cuddy - she needs a babysitter. Wilson realized that House has drugged the grape soda from the minibar, and just before he passes out he tells House that Cuddy is better off without him.

They prepare to give the patient amobarbital. After she is dosed, she starts talking about the comic book artist. However, her heart rate is increasing. She admits she realized he gave her a tablet and then started touching her. The father wants to kill the artist, but Foreman has been monitoring the patient's pericardial blood flow and realizes she's still lying.

House goes to see Cuddy and wonders why it is so quiet with Rachel in the room. House offers to babysit, but Cuddy says Rachel is in day care. However, he then hears Rachel cooing. He walks in and finds her with Lucas Douglas. They talk about how awkward the situation is and House agrees to leave.

Wilson finally regains consciousness and finds the phone ringing. It's Foreman looking for House, but House isn't in the room. Foreman updates him about the bleeding problem and tells him the comic book artist has a dog so they are treating for rickettsia. Wilson realizes he is late for his talk.

However, a well dressed House is giving the talk instead, and he's giving Wilson's original talk. Wilson is still looking for his pants. House is obviously taking the heat for Wilson's talk to save his career. Wilson finally shows up and realizes what has happened. House then adds something - that he never does anything less than his best. Although there are many questions, House dodges them all. Wilson finally realizes that the crowd still thinks House is Dr. Perlmutter.

Wilson catches up with House and tells him about the rickettsia. They then talk about House's deception. House wonders why Wilson is angry with him. He thinks that Wilson is more upset about his patients dying all the time then not being able to give his speech. As he's telling Wilson how guilt is affecting him, he thinks of something and calls his team.

House has realized the blood transfusions are killing the patient. She got vibrio vulnificus from oysters. The patient denies it, but she's lying again. Chase wonders why no-one else is sick, but House has an explanation - she's more susceptible because she has hemochromatosis as well. Because they thought she had bulimia, she got iron supplements, which made it worse. When she started bleeding, they gave her more blood, which contained even more iron and made the bleeding even worse. She needs treatment for the vibrio and chelation for the hemochromatosis.

Cuddy, Wilson, House, Lucas and Rachel have dinner together and House asks how Lucas and Cuddy got together. Cuddy hired Lucas to see who was skimming money from accounting. House wanted to know why they kept it secret. She says she likes to keep her private life private. Lucas starts rattling off about all their problems and can't shut up. He offers to buy House a ginger ale and House accepts.

The patient starts to improve. However, her parents are leaving her to her own devices again. The patient finally admits that she never knocked on the artist's door and merely left the journal next to it.

House watches Cuddy and Lucas play with Rachel. He seems resigned to the fact and wants to raid the minibar again. Wilson tells him that House often needs to hear that he's right from someone else and forgives him for giving the speech. It turns out Perlmutter was in Toronto, giving him an alibi, and House won't be recognized because he hasn't been at a conference in fifteen years.

Cameron and Chase start talking. He once again denies having an affair. Cameron offers to help because she knows, whatever it is, its eating away at him. Chase admits to his deceptions that caused the death of President Dibala.

Vibrio vulnificus is very rare, with an incidence of about 1 in 1 million every year, or about 300 cases per year in the United States. It is very difficult to get infection and most people with a normal immune system can easily fight off the bacteria without help. It mostly affects people who are immunocompromised or already have liver disease.

• The title of this episode is a fairly common phrase, most famously used by former United States Secretary of Defense Donald Rumsfeld. Known unknowns are simply things that people know they do not know.
• The name of the band Jordan and Phoebe follow in to the hotel is "Pharmacide".
• Victory or death is one of the most common battle cries and fighting mottos in the world.
• The episode contains one of the hallmarks of one of its writers, Doris Egan - House travels out of Princeton.
• The conference is entitled "Pharmacology and Public Policy".
• Ramadan is the month of fasting in the Islamic calendar, where Muslims refrain from food during daylight hours.
• The Adirondacks are a range of geological features in north-eastern New York State. Unlike other mountains, they were not formed by tectonic forces but were instead revealed when the surrounding land eroded away to expose harder igneous formations from about one billion years ago.
• The convention scenes were filmed at the Lake Arrowhead Resort & Spa in Lake Arrowhead, California, about 80 km (50 mi) east of Los Angeles, on the other side of the mountains from San Bernardino.
• Eddie Money was one of the most successful rock performers of the 1970s and 1980s, with ten top 40 hits during that period of time, Two Tickets to Paradise reached #22 in 1978.
• Rutgers is Rutgers University, the largest university in New Jersey with over 50, 000 students at several campuses throughout the state.
• Shanghai is the largest city in China and is the most heavily influenced by Western culture.
• Patty & Selma are the sisters of Marge Simpson on "The Simpsons". "House" was one of several Fox shows to mention "The Simpsons" that week, as that show was celebrating its 20th anniversary. The reference was a clue in a scavenger hunt contest run by Fox during the week. The "always smokin'" comment refers to their habit of chain smoking.
• Lars Ulrich is the drummer for Metallica.
• Hippocrates was an ancient Greek physician and is widely regarded to be the father of Western medicine and the author of the Hippocratic Oath.
• Lots of drumming references. The "high-hat" is a pair of cymbals on a stand that is activated by a pedal.
• Head banging is shaking one's head violently in time with the music.
• Stiletto was portrayed by Megan Taylor, who also worked as a production assistant on the series.
• Bushido is the term that describes the life of a samurai in Japanese culture. The term is also used in Wilson.
• Bruce Springsteen is a popular entertainer who was born and raised in New Jersey.

House's outfit for the '80s party at the medical conference.

• House attends the '80s party dressed similarly to Prince George. Hugh Laurie (Greg House) played Prince George in the British comedy sitcom Blackadder the Third which aired in his native United Kingdom from September 17 to October 22, 1987. House's outfit could also be a nod to Hugh Laurie's appearance in Annie Lennox's music video 'Walking on Broken Glass' where he wore similar clothing.
• Cuddy's outfit at the '80s party is based on Jennifer Beal's character from Flashdance. Lisa Edelstein sang the soundtrack from Flashdance in the television series Almost Perfect.
• Some of the other guests at the '80s party also reference films from the 1980s. One man is dressed up in a Ghostbusters costume, and another like John Cusack's character from Say Anything... with a boombox over his head. Say Anything... is also referenced in The Tyrant and Ghostbusters is referred to in Two Stories. There was also a marshmallow man in Ghostbusters.
• Jane Fonda is an Academy Award winning actress who released a best-selling line of workout videos.
• "Time After Time" is also the song that Napoleon and Deb slow dance to in Napoleon Dynamite.
• The Times is a reference to The New York Times.
• Angela Merkel was the Chancellor of Germany.
• A fjord is a narrow inlet formed by glacial erosion. Although found in many places, they are most commonly associated with Norway. In the Monty Python "Dead Parrot Sketch", the salesman blamed the parrot's lack of movement on "pining for the fjords".
• Toronto is the largest city in Canada. The band Metric, which plays the song in the opening scene, was founded there as well.
• Skinny dipping is the act or practice of swimming in the nude in a pool, body of water or hot tubs.
• House refers to the patient as a "Gossip Girl", a reference to Gossip Girl, featuring Leighton Meester.
• A Flock of Seagulls was one of the most popular new wave bands of the early 1980s.
• The boiling frog metaphor raises its ugly head. In reality, A frog will try to get out of gradually heated water when the temperature becomes uncomfortable - a relatively low 80 degrees Fahrenheit (far cooler than a typical bath).

• "Sydney" is misspelled on the poster for the 10 Nation Tour.
• After Jordan falls to the ground during the scene she talks to her girlfriends, the camera shows her "swollen hands", which are now completely normal in size.
• House asserted at the end of the episode that he hadn't attended a U.S. conference in 15 years - this was why there was no chance he would be recognized. This doesn't quite match up with events from five seasons ago. House may have forgotten - or wanted to forget - that he attended the National Cardiology Conference in Season 1's "Role Model", and gave a speech at Edward Vogler's request. While the location of that conference isn't revealed in that episode, the name of the conference makes it likely it was held at a stateside location.
• When House and Wilson argue after House delivers Wilson's paper, House's collar keeps switching back and forth from inside his jacket to outside his jacket.

Physician assisted suicide:

Although it has nothing to do with the main patient in this episode, the series once again takes on the issue of euthanasia. The subject was first visited in Season 3's Informed Consent, where it directly affected the patient.

Very little has changed since this episode was aired in 2009, but some places, most recently Quebec, Canada, have attempted to set up mechanisms by where the life of terminal patients can be ended through medical means. However, in most places, doctors who engage in "assisted suicide" face stiff prison penalties, something that Remy Hadley learns all too well in Season 7.

As Wilson points out, there is active debate among both physicians and non-physicians about the ethics of end-of-life care. However, physicians rarely discuss their experiences openly as, once they get too vocal, they face the same scrutiny that Dr. Jack Kevorkian drew - scrutiny that eventually resulted in a ten-year prison stint.

Probably not by coincidence, 2009 was also the year that generated one of the key myths about the Affordable Health Care Act ("Obamacare"): that it would set up death panels where bureaucrats would make decisions about end-of-life patients, determining whether or not they would receive health care at all. However, that debate focused on another issue: the cost of intensive care for end-of-life patients (outside of the United States, it's far more common for patients to only receive palliative care).

However, an oncologist like Wilson would be all too familiar with the pain faced by cancer patients and other end-of-life patients. Even with morphine, which often has a lesser effect the longer it is used, most patients are in intolerable pain. Ironically, much of the pain felt by cancer patients is not due to the cancer itself, but to the side effects of treatments such as radiation and chemotherapy.

One thing is certain: setting up a legal assisted suicide regime will probably not solve all the issues. As with other controversial measures, opponents will often find a way to make the provisions unworkable in practice, and there are individuals who undoubtedly will abuse the system for their own gain. The restrictions on abortion in many U.S. states certainly makes it much harder to obtain what is, in theory, a perfectly legal medical procedure. Similarly, Canada's medical marijuana regime resulted in relatively few patients receiving the drug as doctors who wrote prescriptions for it soon drew scrutiny from the police and their own medical regulators.

Leaving euthanasia aside, the patient also created issues often seen elsewhere in the series. At the beginning of the episode, the doctors are faced with treating a minor. Later, they are dealing with a patient who, although not deliberately, is being deceptive. The team has frequently dealt with both unaccompanied minors and liars in the past (and even a fair number of lying minors), but Jordan's condition poses some unique challenges.

Treating minors:

As with Sophia Isabel Velez in Emancipation and Callie Rogers in Runaways, Jordan may be a minor and technically under the control of a guardian, but she is also independent with very little adult supervision. However, the question can often be raised as to whether any patient can truly consent to procedures, and minors are also at risk because they are often not aware of even common risks. As this episode made clear, even what appears to be the safest of treatments (iron supplements) can cause havoc in a patient when they have a pre-existing condition.

Luckily, in this episode, both Jordan and her absent parents are co-operative. However, this isn't always the case and, even here, the parents aren't much help. We have seen in several episodes that a minor's problems are due to things they are keeping from their parent but, luckily, that isn't the case here either.

One thing that does cause the doctors some concern is the parents' seeming indifference to Jordan when she isn't in crisis. Once this crisis is over, they seem content to leave Jordan to her own devices once again. Surprisingly, Jordan is fine with this and seems well-adjusted for a "credit card kid".

Liar Liar:

The whole series is based on patients not telling the truth, and you would think that this case would be irresistible to House. Still, the theme of patients not providing reliable information is summed up best by Chris Taub in Nobody's Fault:

"No, he thinks they're crucial. He just doesn't think being in the same room as the patient is crucial. House thinks avoiding patients allows him to stay as objective as possible. He's not wrong." ―Taub, explaining House's approach to patient histories

In modern medicine, with an approach that requires the collaboration of the patient in treatment, dishonesty will go deeper into the heart of the professional relationship between the doctor and the patient. It is not uncommon nowadays for doctors to refuse to see patients who refuse to follow their treatment regimen (after making sure they're passed off to another physician if necessary).

But doctors know that dishonesty affects their ability to diagnose a patient properly, and they often realize (as in this case) that the lack of honest responses makes any treatment risky. Tests can only tell the doctors so much and in real life merely narrow down the range of possible diagnoses.

But what if the dishonesty is not due to any conscious decision of the patient? In this case, the dishonesty is a pathology - a symptom of some condition, not a behavioral defect. Psychiatrists are used to patients who are delusional, and it doesn't stop them from making treatment decisions, even over a patient's express objections. Here, at least, the parents are able to be somewhat more objective than the patient.

Objectivity:

If Cameron has one character flaw, it has to be that she is the most judgmental character on the show. However, her judgment cuts both ways. We have seen her show compassion to patients who turn out not to deserve it, and conversely to turn on patients who similarly are undeserving.

Once Cameron takes a dislike to Jeffrey Keener, her objectivity is compromised for the rest of the case. House might have suspected Keener of wrongdoing, but he never would have jumped to conclusions or based every subsequent diagnosis on the belief Keener must have done something wrong. Luckily, Chase and Foreman are there to put the reins on her, but had she been in charge of the case it is likely that she would have kept looking for a toxin or psychological cause to Jordan's illness.

House's absence here shows the importance of his approach - treat the disease and not the people. In the few situations where House has lost his objectivity, he often does things he wishes he hadn't. There are lots of other situations where his objectivity has kept his colleagues from going off the deep end (and that includes his saving Wilson in this episode).