Bones - Episode 4.06: The Crank in the Shaft

A leg is found in an elevator so Booth, Brennan and Cam go to the scene. Back at the lab, the team is assisted by "grad of the week" Colin Fisher, a depressed man in his mid-20s who has a pierced lip and wears black nail polish. Hodgins tries to avoid Angela. The latter asks Brennan for suggestions on how to act around Hodgins. Angela eventually turns to Sweets for help. Booth tries to get Cam to write him a doctor's note so he can get a nifty new office chair.

Source: SpoilerFix