Lou George

When Ted and Barney argue about who has "dibs" on a hot girl, Ted realizes that she is there with Cindy (guest star Rachel Bilson), a girl he previously dated who is also the roommate of his future wife. Meanwhile, Robin is heartbroken over Don, and Marshall can't keep quiet about his desire to start a family.

When a simple procedure goes awry, Elliot seeks advice from Dr. Kevin Casey (Michael J. Fox); Turk asks JD to be his best man at the wedding.

The NCIS team must rely on Twitter for a case involving a missing Navy Lieutenant. Meanwhile, McGee misplaces his badge but withholds the information from Gibbs and the authorities.

It's Science Fair time and Josh is sure that this year, his is the project to beat. But when Mindy Crenshaw makes a surprise return, sparks fly in the most unexpected places.

After Mindy tells Josh she loves him, Josh turns to the only logical place for advice: Drake.