I don't know a single 'Grey's Anatomy' fan that isn't going through withdrawal. We haven't had a new episode in a month, and the teases and scoops and sneak peek videos have been enough to drive anyone to a rage-filled Seattle Grace shoot-out. (Too soon?)Never fear because there's finally a new episode this week (Thurs., March 24, 9PM ET on ABC). I caught up with star Chyler Leigh, the forever in flux Dr. Lexie Grey -- who was last seen showering with sexy Dr. Jackson Avery (Jesse Williams) -- to find out what's coming next.First up, there's this week's big baby shower episode for Callie, complete with the typical shower games and, in true 'Grey's' fashion, some major drama.Then next week we'll finally see The Music Event, 'Grey's Anatomy''s much-anticipated 'Song Beneath the Song' musical episode, in which Leigh will be singing Anna Nalick's 'Breathe (2 AM),' alongside cast performances of The Fray's 'How to Save a Life,' Snow Patrol's 'Chasing Cars' and other songs that the show has helped make famous.