Lue is sleeping at home in his bedroom dreaming that a demonic hag has entered his room and started choking him. His mother Lida tries to wake him up, telling him that there’s no one there, but discovers that her son isn’t breathing.
House arrives at the hospital and Foreman tries to tell him about Lue’s case. House would rather talk about his sex dreams concerning Dominika and isn’t interested in Lue until Foreman mentions that the boy hallucinated a demon trying to kill him, and that Lue and his family are Hmong. House digs out boxes of cases on Hmong Syndrome, which involves persons of that nationality dying in their sleep of respiratory failure. Park dismisses the importance of dreams and suggests environmental contamination, and House wonders why she’s so defensive. Chase is interested in the fact that the boy imagined being attacked by a demon. House assigns Park and Chase to administer antibiotics but Park asks to be on the team checking the home since it was her idea. House agrees but figures that she’s reluctant to be around Chase because she was having sexual dreams about him.
As Adams tests Lue, Chase asks Lida about the demons and she explains that as an engineer, she doesn’t believe in evil spirits.
House interrupts Wilson performing a breast check for cancer and drags him out into the hallway to tell him about his sex dream concerning Dominika. Wilson isn’t interested and tells him to leave.
As Taub and Park check the home, they discuss her dreams and he doesn’t see it as a cause for concern. Taub suggests that her dreams might just represent her love of her work. They smell something damp from upstairs and check out Lue’s bedroom, and discover that someone has dismembered a pig and hung papers with symbols from the ceiling. They go back to the hospital and tell Lida, who realizes that her father Xang performed a ceremony with the pig. Xang is at her son’s bedside and he admits that he did what Lida should have done weeks ago.
Lue’s heart stops briefly and they revive him, and then go back into differential with the new symptom. They’ve learned that Lue’s father, Kao, beat a man to death with a sledge hammer and was sent to prison. Xang believes that demons possessed his son and drove him to murder, and that now the demons are stealing Lue’s soul. Adams suggests PSTD but Park points out that Lida never told her son what happened to Kao. House tells them to check the pericardium and test the samples from the home for toxins. As they go, Park makes sure that everyone knows that she’s very happy with her job. House then goes to Wilson office and tries to talk more about his dream, but Wilson informs him that it’s guilt over throwing away Dominika’s naturalization letters. He tells his friend to stick to the truth and orders him out.
As Chase and Park work together on the tests, she jumps when he reaches for a nearby test and he suggests that her having sex dreams about him is normal. She’s offended by the comment, and even more when he says that he doesn’t have sex dreams about her. Taub and Adams meet with them and confirm that the echo was negative, and now Lue is suffering from abdominal pains and constipation. Chase suggests a thyroid problem and proposes a biopsy.
That night, House and Dominika have (stolen) takeout in his office. When she realizes that it’s stolen, House admits that he knows her pretty well. House starts to tell her the truth but then lies and says that she may have to wait as much as a month to hear back from the INS. Dominika is eager to be naturalized even though it’s been fun staying with House, and House suggests that they shoot someone together.
As Adams administers a local anesthetic so they can do the biopsy, Lue starts speaking in what sounds like gibberish. However, Xang says that it’s Hmong and that the demon is speaking through the boy, and Lida explains that Lue doesn’t know any Hmong. Back in differential, Taub begins to wonder if Lue is possessed, but House points out that none of them understand Hmong and Xang is the only one who translated. House figures the grandfather wants to find a way to absolve Kao of his guilt so blames everything on demons. Chase suggests a neurological problem and Park agrees, and House wonders why they’re agreeing when they shouldn’t even be able to look at each other. While they both pointedly look at each other to demonstrate they don’t have an issue, Adams suggests encephalitis and House tells them to run a MRI to confirm.
Chase goes to Lida with their new diagnosis, but Xang believes that they’re wrong. He says that Lue is having the same dreams that Kao had before he killed the man, but Chase warns that scaring Lue won’t help him get better.
As Taub and Park run the MRI, Park lies and says that she had a sex dream about Taub. He’s flattered and interested, and Park says that’s how Chase should react. Taub says that they make a great couple and wishes them well, even though he thinks there too different for each other. Park takes offense at that, insisting they’re not that difficult, and Taub tells her not to let House ruin whatever she and Chase have.
House takes Dominika to a shooting range and she hits the bull’s eye repeatedly, admitting that she served one year with a police unit. He gets a text from the team confirming that the MRI was negative and Dominika asks why he can’t believe in demons when he believes in quantum particles. Impressed, House asks how she knows about quantum physics and Dominika explains that she has been reading his books in her spare time.
Lue has another dream, this time of his grandfather choking him to drive out the demons of the air. Taub and Lida come in and wake him up, but discover that he has bruises on his neck as if someone was actually choking him. When Taub reports the incident to the team, House figures that the bruises came first and that the dream followed conforming to the injuries. He’s more interested in Park’s dreams and accuses Chase of liking the attention from her. House finally focusses on the case and suggests fibrosis, and tells them to do a liver biopsy.
As Taub and Adams perform the biopsy, Lida admits that she’s reluctant to accept that demons are possessing Lue’s problem, but points out that so far they haven’t been able to provide a medical explanation for the symptoms.
Chase is dozing in the lounge when Park comes in and tells him that they have the biopsy results. He insists that he just wants her to treat him like a friend, not a sex partner, but she gets increasingly angry. They insult each other and then embrace. Park throws Chase back on the couch, rips open his shirt... and he wakes up from his dream. Park has just come in and is calling to wake him up, and he says that he’ll be right there.
The biopsy shows no signs of fibrosis and they start to inform Lida. However, an ICU nurse calls them into Lue’s room and they watch as he briefly levitates off the bed and then drops back down. When they tell House, he dismisses it as a magic trick and proves he can do something similar. House then focusses on the fact that Chase is avoiding Park as much as he can, when the day before he wasn’t. Chase tries to focus on the case and suggests hypocalcemia and House agrees... and then tells Park that Chase is having sex dreams about her.
As Chase and Taub prepare the treatment, Lida says that nothing they’ve done has cured her son. She explains that her grandfather believes that the ceremony in Lue’s bedroom failed because Lue wasn’t there. She’s decided that Xang is right and that she wants to check Lue out so that they take him home and treat him. When House hears about her decision, he complains to Foreman, warning that he’d quit rather than let them give into superstition. Foreman points out that it’s no worse than a priest visiting a patient, but has second thought when House points out that the exorcism will involve animal sacrifice. The administrator goes to Lida and threatens to keep him, but she warns Foreman that she’s checked with a lawyer and the hospital can’t legally hold Lue and violate Lida’s religious beliefs. Foreman asks her to give him 24 hours and Lida agrees.
When House comes home, he finds Dominika upset about a phone call that she just received. She holds up a letter and House starts to apologize, but she then explains that her uncle mailed to tell her that he was committing his wife. Upset that she was kept out of the loop by her mother, Dominika hugs House and asks if he’s going out, and House says that he can stay in and be there for her.
Lue’s continue deteriorates and Lida insists that the hospital let Xang perform the Hmong ceremony. As he begins the exorcism, the team meets in differential. House is disgusted with the entire situation and is giving up. He believes that if even if they do manage to cure Lue, Lida will credit her grandfather anyway and all they’re doing is encouraging superstition rather than science. House would rather see Lue dead than let that happen. However, they discuss PDA as a possibility and House insists that the lack of evidence may indicate that Lue has an infected ductus since it fits the symptoms. Adams points out that they can treat the malformed duct with ibuprofen. House refuses to let them treat with ibuprofen and tells them to stick to their original diagnosis, and walks away.
Adams checks on Lue and discovers that he’s non-responsive. As they try to revive him, Lida realizes that they’re wrong again and calls Xang. The grandfather performs the Hmong ceremony in the hospital room while the team meets for differential. House isn’t interested since Lida has given up, and figures that if they do cure Lue then Xang will take the credit. He figures that Lue is better off dead if Lida embraces faith over science. House suggests PDA even though he’s not an infant and hasn’t demonstrated any symptoms. He figures the antibiotics may have set it off and Adams notes that the treatment is ibuprofen. House refuses to let them treat and Chase points out that he’s letting a patient die to prove his point. In response, House says that he’ll respect their diagnosis but refuses to let them treat with ibuprofen.
When Adams and Taub go to check on Lue, the boy’s system gives out. Adams decides to ignore House and gives the boy ibuprofen.
Later, Dominika finds House in bed drinking and sulking. He worries that either he’s killing his patient or religion is. Dominika starts to undress to comfort him, but House’s phone rings. He tries to stop her, but Dominika picks it up and realizes that it’s the INS. They say that they have her naturalization papers but they also confirm that they’ve been sending her letters for the last month. House tries to apologize but Dominika walks away from him.
Lue’s condition improves and Lida credits her grandfather’s exorcism. She doesn’t believe Adams when the doctor explains that it’s the ibuprofen that saved him. As Taub and Adams look on, Taub admits that they thought two things were impossible, and all they know now is that one of them wasn’t.
Dominika packs her belongings and leaves.
Park catches up to Chase as he leaves for the day and asks if she was good in his dream. He still insists that dreams don’t mean anything, but Park suggests that it means that they could trust each other. Chase concedes the possibility and Park passes gas to see if it’s true.
When House comes to see Wilson and complain about his lie, Wilson finally admits that the tests came in that morning. He is positive for stage II thymoma cancer.