S8, E6: Through Lexie, Meredith tries to get Derek interested in a patient's rare brain tumor; Callie ends up being annoyed when Mark and Arizona finally form a friendship.

Starring Lee Majors, Marilu Henner, Dash Mihok
S8, E6: Through Lexie, Meredith tries to get Derek interested in a patient's rare brain tumor; Callie ends up being annoyed when Mark and Arizona finally form a friendship.