Calista and Mary: Why So Serious?

11/18/2008 6:45 AM PST BY TMZ STAFF
Here's 44-year-old "Brothers and Sisters" star Calista Flockhart (left) at an event in Santa Monica this weekend -- and 71-year-old TV icon Mary Tyler Moore (right).
Calista and Mary
Neither one ever played the Joker.

We're just sayin'.