Dr. Cox is unable to diagnose a recurring patient of two years. He gives J.D. and Turk the patient's urine sample to take to the lab, however they serendipitously diagnose him when they accidentally leave the sample out in the sun too long, causing it to turn purple. J.D. then Googles "Purple pee" and discovers it is a symptom of acute intermittent porphyria.
Ted, who has just heard the news of Dr. Kelso's forced retirement, streaks through the halls of the hospital celebrating his freedom. He runs outside and is hit in the parking lot by the Janitor's van, biting off part of his tongue. Dr. Kelso gets all "nostalgic and crap" with an intern named Boon, reminiscing about his 40-year career at Sacred Heart, from his internship to his lonely days as Chief of Medicine. Later on Boon reassures the staff that Kelso does really care about the hospital.
Carla and Elliot attempt to persuade the board not to force Dr. Kelso to retire. They try to gain the support of many of the staff of Sacred Heart but Dr. Cox wants Kelso out and so the staff will not help. Later on Dr. Cox realizes that it is better to have an enemy he knows as Chief of Medicine than one he doesn't. He then agrees to help convince the board to let Kelso stay and the board approves Kelso's position. Upon hearing the news Dr. Kelso retires on his own terms, taking his portrait off the wall, thanks Ted sincerely for his work and drives off into the sunset.