Alyson Hannigan 1989, her first regular role on a TV series came when she was cast in the short-lived ABC sitcom "Free Spirit". As a teenager, Hannigan babysat for the children of her future "How I Met Your Mother" costar, Bob Saget. In 1997, Hannigan was cast to play Willow Rosenberg, Buffy Summers' best friend, on the television series "Buffy the Vampire Slayer". The show became a success, and Hannigan gained recognition, subsequently appearing in several films aimed at teenaged audiences, including "American Pie" (1999), "Boys and Girls" (2000), "American Pie 2" (2001), and "American Wedding" (2003). She also had a guest
Villains (Buffy the Vampire Slayer) Villains (Buffy the Vampire Slayer) "Villains" is the 20th episode of season 6 of the television series "Buffy the Vampire Slayer". An ambulance arrives at the Summers' house to treat the wounded Buffy. Upstairs, the distraught Willow calls upon Osiris to bring the murdered Tara back to life, but the god cannot, because the death did not involve magic. She leaves, learning from Xander that Warren Mears had shot Buffy, but does not tell him that Warren had also killed Tara. Warren celebrates at Willie's bar, bragging about killing the Slayer. The demon bartender tells him that TV news reports