Former "Buffy the Vampire Slayer" regular Michelle Trachtenberg will try out her comedy chops at ABC.

The Alphabet has added the actress to its untitled Washington-set comedy, according to The Hollywood Reporter. Another "Buffy" veteran, Kali Rocha, has meanwhile signed onto ABC's "The Call," as has Kal Penn. The network has also added Adam Goldberg to its drama "Marlowe."

Trachtenberg will star opposite Eric Christian Olsen ("The Loop") in the D.C. comedy. She'll be playing the daughter of a lawmaker who falls in love with Olsen's character, who just happens to work for her dad's nemesis across the aisle.

Trachtenberg played Buffy's sister Dawn for three seasons on "Buffy the Vampire Slayer." More recently she's starred in the movies "Black Christmas" and "Beautiful Ohio" and made guest appearances on "House" and "Law & Order: SVU."

In "The Call," a comedy about a group of L.A. paramedics, Penn will play a hypochondriac member of the team, while Rocha will play the group's boss. The show's cast also includes Jodi Lyn O'Keefe, John Francis Daley and Danny Comden.

Penn appeared on several episodes of "24" this season; that show's producers are also behind "The Call." Rocha, who had a recurring part as the demon Halfrek on "Buffy," currently plays chipper attending physician Sydney Heron on "Grey's Anatomy."

On the drama side, Goldberg will star opposite Jason O'Mara and Amanda Righetti in "Marlowe," a contemporary take on the Raymond Chandler private eye. He'll play an LAPD detective who occasionally helps Marlowe (O'Mara).

Goldberg is currently on the big screen in "Zodiac." His other credits include FOX's "Head Cases," "Deja Vu" and "Dazed & Confused."