Gifted surgeon Addison Montgomery (Kate Walsh) and her colleagues -- divorced couple Naomi (Audra McDonald) and Sam (Taye Diggs) -- must solve a new batch of complex medical cases while contemplating romantic entanglements in this hit spinoff's second season. The talented ensemble cast also includes Amy Brenneman as psychiatrist Violet Turner and Tim Daly as Pete Wilder, an alternative-medicine specialist who makes Addison's heart flutter.