My Common Enemy

S4, E7: J.D. (Zach Braff) decides he won't start dating again until Elliot (Sarah Chalke) does, but doesn't expect the person she starts dating to be his brother Dan (guest star Tom Cavanagh), who's still sticking around after the recent death of their father. When J.D. catches them sleeping together in the on-call room, things get a little awkward between the three. Meanwhile, after Turk (Donald Faison) is diagnosed with Type II Diabetes, he milks every ounce of sympathy out of his friends. Elsewhere, Dr. Cox (John C. McGinley) and Dr. Kelso (Ken Jenkins) get fed-up with Molly's (guest star Heather Graham) perception that everyone is good at heart and seek to prove her wrong. Judy Reyes and Neil Flynn also star.