The doctors reunite to teach med school to a new set of students, but J.D. is not sure after his first day whether he can make a difference and connect with any of his students.

Lucy ignores Dr. Cox's advice not to get emotionally invested in her patients, and learns her lesson the hard way. Meanwhile, Denise is hurt when she becomes emotionally involved with an intern who is only in it for the sex.

When Drew lets Dr. Cox down, he is then forced to turn to JD for help. Meanwhile, Lucy asks Dr. Mahoney to be her mentor, but she is too preoccupied with her own issues as a doctor to help.

J. D. and Turk show up in costume at a med student's party. Meanwhile, Kelso bids a fond farewell to Ted and Gooch.

JD spends his final day as a teacher trying to find out who gave him a negative review, Lucy looks for a "blood buddy," and Dr. Cox tries to convince Denise that Drew has taken charge of their relationship.

Cole reveals Drew's most embarrassing moment when Drew beats him out as the speaker at the white coat ceremony, while Denise turns to Turk and Eliot for more relationship advice.

Lucy struggles to acknowledge that she likes Cole, Dr. Cox and Dr. Turk's rivalry is put aside for a gravely ill patient, and Denise plays a prank on the security guards at the hospital.

J.D. and Elliot's sex life disappears as they get closer to the birth of their child, Dr. Cox refuses to sign his will after a patient dies, and Lucy is terrified of cutting a familiar cadaver for a group exam.

Dr. Cox tries to find out which member of Lucy's study group cheated on a test, Drew gets in trouble when he tells Denise he loves her and then makes the situation worse, and a patient irrationally chooses surgery over treatment.

Turk is jealous when he is upstaged by a talented visiting surgeon, and the study group falls apart when Dr. Cox removes Drew from the group so that Drew can shadow him.

Cole is depressed when nobody but Lucy shows up for his melanoma procedure, Dr. Kelso loses some of personal independence after some tests, and Drew discovers that Dr. Mahoney has the same personality as Dr. Cox.

The med students are thankful when Cole identifies his true calling.