As Dr. Gregory House leaves the clinic, he bumps into Harvey Park in the waiting room, whom he insults when he believes that Harvey spilled a sample of urine onto his clothes. Prodded by Wilson (who informs House that the spilled liquid was really apple juice) House reluctantly goes to apologize. He finds the patient with labored breathing and believes it is merely anxiety until he realizes Harvey's right pupil is blown, indicating a stroke. He calls for a wheelchair.
With a new case in hand, Dr. House has the team analyze Harvey's condition. The patient was in the clinic because he was grinding his teeth. Dr. Cameron, back from hiatus, notes that a blown pupil is usually the result of brain stem edema, but Dr. House notes that is always fatal or at least causes a coma and the patient is still conscious, so it is most likely a stroke to the optic nerve. On the CT scan, Dr. Foreman notes ischemia, death of brain tissue, and suggests an MRI to find the underlying cause, but Dr. Cameron notes the metal plate in Harvey's jawbone, which rules out an MRI as a diagnostic tool. As the plate can't be removed, Dr. House has the team do tests; angiogram to rule out vasculitis, EMG for peripheral neuropathy, a tox screen for drugs, and an echocardiogram for cardiac embolism.
Dr. Foreman discusses the case with Harvey while his friend Annette Raines is by his side. She informs Dr. Foreman that Harvey's parents are dead and he has no other next of kin. Harvey is having trouble with nouns indicating aphasia. His teeth grinding has been going on for six months and he has seen an acupunturist, a shen balancer, a homeopath, a chiropractor, and a naturopath. Dr. Foreman asks for those records. Dr. Chase notices Annette in the room and asks who she is, and Foreman calls her the patient's "guru".
Dr. Cameron explains the EMG test to the patient, who doesn't seem to be concerned about how painful the test might be. He seems to be tolerating the pain very well. However, the EMG was clean. Given the patient's history with alternative practitioners, Dr. House surmises it might be toxic herbs from the homeopath, spine damage from the chiropractor, infection from an acupuncture needle. However, the only abnormal test result was a mitral valve prolapse. Dr. Forman surmises the faulty valved caused a clot that led to the stroke, but they can't find the source of the clot. Dr. Chase suggests a trauma-induced aneurysm, but is brushed off, as there appears to be absolutely no medical evidence to support this theory. Dr. Foreman is sure it is bacterial endocarditis and suggests blood cultures. Dr. Chase argues in favor of the aneurysm again, noting that he heard an unusual noise when he used his stethoscope on Harvey's carotid artery. However, Dr. Cameron argues that an aneurysm would have shown up on the angiogram, but Dr. Chase argues that isn't a certainty. He wants to do another angiogram. However, Dr. House sides with Foreman and orders blood thinners and antibiotics. However, before they can start Harvey on this treatment, they find Annette strangling him. They restrain her until Chase confirms that Annette is a dominatrix, and Harvey is an asphyxophiliac. She explains to Dr. Cuddy and the hospital's general counsel that choking Harvey reduces his anxiety level. Dr. House asks that she be barred from the hospital. Dr. Chase reveals he met Annette before when he had a girlfriend who sexually excited by being burned. Dr. House admonishes Dr. Chase for not revealing that the patient may be sexually excited by pain, which would have made a trauma-induced aneurysm more likely. Dr. Chase suggests vasuclar surgery to find and repair the aneurysm. Although Dr. House thinks that Dr. Chase is right, he orders blood thinners and antibiotics even though Dr. Foreman now sides with Dr. Chase because if it is endocarditis, surgery will kill the patient. If Harvey has another stroke, they will do the surgery.
The team gives Harvey blood thinners and antibiotics. Dr. Chase tests his grip strength, but notices that he has weakness in his right arm and hand. Harvey continues to have mini-strokes. Dr. House stops the treatment and directs his team to book a vasular surgeon. Dr. Chase explains to the patient that the strangulations most likely caused his condition. He's upset that he can't see Annette. Dr. Chase tries to dominate Harvey, but he won't consent to surgery. They give the patient anti-depressants to see if that will change his mood. Dr. House orders Dr. Chase to find Annette, who is barred from re-entering the hospital, to convince the patient, but even she can't do it - the patient's personality has changed and he becomes insulting and combative. He has another stroke and crashes, entering into a coma.
The general counsel will not let House proceed with surgery once the patient has withheld consent, and won't let him proceed even in an emergency without a court order. They can't get a court order unless House can show the patient has no next of kin. The team want's to search obituaries and funeral homes, but Dr. House thinks the parents are still alive - it is unlikely the parents, who were accountants, would leave their only son so impoverished he lives in a bad apartment in a bad neighborhood. Dr. Chase thinks it is plausible they disowned Harvey when they found out about his asphyxophilia. Dr. Chase and Dr. Cameron head to Harvey's apartment, finding various S&M gear, clothing and an address book. He lists Annette as his emergency contact. Chase also notices a slew of Tic Tacs and takes some for himself before he leaves. Cameron finds a high school yearbook.
The team calls people by the name of Park in the neighborhood of the high school. Dr. Chase finds them, but once he mentions his name, they hang up. Dr. House calls back saying they need someone to identify Harvey's body. They come in, but are enraged by the deception and report it to Dr. Cuddy. Dr. House argues they are merely early - it's only a matter of time before Harvey dies. However, they are unwilling to help their son, due to his lifestyle. Dr. House convinces them that even though they are humiliated by his sex life, it would be more humiliating for them to have him die because they would not sign a consent form and he would let everyone know. They relent and surgery is scheduled for first thing the next morning.
After surgery the next day the surgeon informs the team that there is no sign of an aneurysm or any other vasular problems. Still, Harvey is having strokes. Dr. Cameron wants to start the blood thinners again, but given Harvey's condition, he will probably suffer fatal internal bleeding. With a lack of any other options, Dr. House orders another angiogram and another echocardiogram and a full body scan to look for clots.
However, Dr. House realizes after seeing someone use a breath freshener that Dr. Chase has been eating Tic Tacs since he came back from Harvey's. Dr Chase admits he took them from Harvey, but that he had an entire drawer full. Dr. House wonders why Dr. Chase didn't find a drawer full of mints relevant to Harvey's condition. The Tic Tacs were a sign that the patient was trying to cover bad breath. Dr. House required Dr. Chase to smell the inside of Harvey's mouth, which smells like old vomit, pointing to fulminating osteomyelitis, an infection of the jaw which most likely dates from the original break. Infected tissue from the jaw breaks off, blocking blood flow to the brain, leading to Harvey's strokes. The metal plate would hide it from their scans and infections in the jaw bone don't show up on blood tests. House confirms the diagnosis by inserting a needle into Harvey's jaw and drawing out pus. He schedules surgery to remove the infected jawbone and Harvey recovers.
Before he is discharged, Dr. House tells Harvey and Annette to stop the strangulation because of the health risks. She states it is not simply about pain, but rather "being completely vulnerable to another person". Harvey asks if his parents came to see him. Dr. House doesn't answer.