Stewart Nozick is lying in the hallway of his apartment, the floor covered with rose petals. EMTs break in and administer emergency treatment, then put him on a stretcher and take him out. Once outside, Stewart panics and rips himself free, runs inside, and slams the door shut.
Cameron tells House and his team about the case, including the fact Stewart has had three seizures and crushing headaches. House orders a scan but she explains that Stewart is an agoraphobe after he was shot and his girlfriend killed during a mugging seven years ago. Cameron met him as part of an outreach program, although House suggests she's trying to get back on the team. He notices Cuddy outside and goes to talk to her. She wants to talk about the night before when they kissed but he isn't interested. She thanks him for not taking advantage of her. Once back in the meeting, House boasts that he had sex with Cuddy so everyone figures he's joking. House suggests they provoke a seizure and locate the focus via EKG, then orders them to search Stewart'a apartment.
Cameron takes the team to Stewart's house but he only lets one person come in to provoke a seizure while the others search the house for toxins. Cameron prepares to provoke a seizure and Stewart asks for a second. He recognizes her from the outreach program and when she tries to sympathize, he says he has everything he wants in the house and she doesn't know him.
Wilson comes to see House and figures out he actually did have sex with Cuddy. House plans to ignore her and is busy itching a mosquito bite. Wilson wonders why House hid it from him but House interrupts to take a call from the team, who have found nothing and haven't set off a seizure. As he lances the mosquito bite, House is interested in discussing Cameron and Chase's love life and the fact they're not engaged and only meet at Chase's place. When House determines that Stewart seized in the hallway, he decides to bring the outside to Stewart. House arrives with some patients from the ER looking for a house, and finds that only Taub is there. House notes that he shouldn't be there and takes the patients in to inspect the bedroom. Stewart feels stomach pains but the readings show it isn't a seizure.
The team runs a differential and finds a partial small bowel obstruction. They need to do exploratory surgery for a biopsy of Stewart's bowels but Stewart ordered them out. House warns Stewart that he has a blockage that could rupture his intestines but Stewart refuses to go outside. House compromises and suggests Chase come to the home to operate. Outside, Cameron objects and House explains they'll have Chase come to operate, administer anesthesia, and then they'll take him to the hospital. Cameron thinks it's immoral but eventually gives in. Chase arrives and as they begin the operation, Stewart says Cameron is a good person. As soon as Stewart is out, they take him to the hospital.
Wilson meets with Cuddy in the cafeteria and she quickly admits she kissed House. She insists they're just friends and Wilson wonders why she doesn't get involved with House. Cuddy has given a lot of thought to the fact they'd eventually turn on each other and it would end badly. He notes that might not necessarily be bad. Cuddy says she'll be more careful and gets a pager beep.
Cameron and Chase are bringing Stewart in and Cameron suggests they go to her place and he stay over. Chase is puzzled, but Cuddy catches them, aware that they took the surgical equipment. She brings them in and House is curiously passive as Cuddy notes it's setting them up for a lawsuit. House notes he doesn't care what happens as long as Stewart gets post-op. As they leave, Cuddy notes that House's hand is bleeding from the mosquito bite but he disregards it. Meanwhile, Cameron wakes up Stewart so he doesn't have a shock later. He panics and rips out the IV and starts bleeding from the neck. Chase returns and manages to get the bleeding stopped.
Stewart calls his lawyer and forces them to release him, and the lawyer now holds the health care proxy and they still don't have a diagnosis. Cameron insists she made the right call but Cuddy takes them all off the case. Cameron wonders why House didn't object but he figures it's easier to ignore her and orders treatment for the blockage. Chase wonders why Cameron is pursuing the case when they've been taken off of it, and why she's trying to get involved with House's team again. She pointedly notes that she quit: Chase was fired.
Cameron goes to Stewart's house and apologizes, then convinces him to let her in. meanwhile, Wilson talks to House and says that things are different between House and Cuddy now that they've kissed. Wilson figures House is scared but House wonders why Wilson is so worked up about it. Wilson suggests that House should date her but House figure Wilson is trying to live vicariously through him and wants to make House miserable because Wilson is miserable.
Cameron reports the drugs aren't working and suggests they do the surgery at Stewart's home for real. They need a surgeon and Chase won't go near it, so House asks Taub to do it and they begin with Kutner assisting. They remove the bowel for biopsy and determine he has Whipple's Disease. As they prepare to cauterize a bleeder, they ignite gas buildup from the blockage. They put out the fire and put Stewart on antibiotics for the Whipple's.
As Cameron goes over the case at Stewart's house, Chase brings her coffee and suggests he stay at her place. She says he can't because she's working on Stewart's case. Before they can pursue the matter, Cameron is called to Stewart's bedroom: he says his legs are numb.
The paralysis eliminates Whipple's as a diagnosis and Foreman concludes he has Celiac and isn't absorbing nutrients. House tells them to force-feed Stewart wheat. The process is painful, and Cameron believes House ordered it to force Stewart to change his mind and come to the hospital. She says they can do a painless blood test but Foreman notes force-feeding is valid and they go ahead with both tests.
Wilson visits Cuddy and admits he has feelings for her. She agrees and offers to have dinner, and then suggests they just have sex in front of House's office. She figures that Wilson is trying to make House jealous so he'll have a relationship with Cuddy. She thanks him for the attempts… and tells him he's an idiot.
Cameron suggests that Stewart has post-traumatic stress disorder and he says he's had it ever since he's been a child. The only thing that led him to go outside was meeting his girlfriend Angela.
House goes to see Taub as he runs the blood tests, and dumps out the blood. Taub figure House wants him to slow down the test and the increased pain will force Stewart to come to the hospital. He tells Taub to restock Stewart's morphine with saline. When Taub wonders why he'd do that, House says his wedding is on the rocks, which is why he's putting in the extra time. Taub says he's sleeping on the couch but will do it anyway.
At home, House sets up a propane tank to emit gas and smoke out the mosquito. The mosquito lands and House tries to hit it, knocking the tubing loose. He chases it into the kitchen where it lands on the stove. He tries to hit it again and turns on the flames. The propane tank explodes… and House wakes up from his dream. He goes to see Wilson, who thinks that House is imagining things and he itches his hand when he thinks of Cuddy. He suggests that House is afraid to try a relationship but House insists he isn't rationalizing. He goes to visit Stewart for another check and Stewart's heart stops. House calls the lawyer to inform him they have a medical emergency and they need permission to take Stewart to the hospital. The lawyer agrees but Cameron revives Stewart and tells House to cancel the ambulance.
Taub puts in a temporary pacemaker to stabilize Stewart's heartbeat but it's a temporary measure. House believes it's a poison and when the team says the house is clean, he asks Stewart how often he washes the tub, and if it's with bleach and ammonia. House figures the combination of chemicals make chlorine gas, and Stewart weight loss from stress is reducing the amount of fat to absorb the gas, causing his illness.
Cameron goes to Chase to see if he'll put in a permanent pacemaker at Stewart's home, but he refuses. He knew she knew he'd say no and asks what's wrong between them. When she refuses to discuss it, he says that he has them stay at his house because he can tell she doesn't want him at her place. She kicks him out every morning and never offers him a drawer or closet space. He knows she's reluctant to get involved because of her husband but won't chase after her forever.
Cameron calls House to inform him that Stewart's signs are dropping. He tells Cameron to call Taub to get some morphine there, but Cameron realized House switched the morphine for saline and gave Stewart morphine. When House realizes Stewart was having abdominal pain even on the morphine, he checks the blockage on the x-rays. He goes to Stewart's house and shows her the x-rays, which show a bone mass that is actually lead. House opens up Stewart and reveals several pieces of lead. The hollow point bullets the mugger used hollow-point bullets and fragments lodged in Stewart's hip bone. They finally started to dissolve, causing all the symptoms. Cameron wonders if the lead poisoning caused the agoraphobia, but Stewart insists that he's fine and doesn't need to change. Cameron wants his life to be better but House says that Stewart is lying and he's not happy. The rose petals in the hallway, Stewart dropped them as eh was preparing to go to his girlfriend's grave on her birthday. House tells Stewart to do something but don't believe his rationalizations.
Cameron confronts Chase and admits he was right, and that her husband's memory is still affecting him. She tells him she's cleaned out a drawer for him. They go to her apartment.
House is playing the guitar at home when he finally sees the mosquito. He prepares to smash it but then blows it away and decides to set aside his own rationalizations. He goes to Cuddy's house.
Stewart braces himself… and steps out of his house.
Taub's wife goes to him and they hug.
House looks at Cuddy from outside. She doesn't notice him. He considers for a few moments, then turns and leaves.