Proof

…both in dramas, such as Proof (2002) and All My Sons (2006), and in musicals, most notably Rent (1997), Cabaret (2003), Stephen Sondheim’s Assassins (2004), and concert stagings of Sondheim’s Sweeney Todd (2001) and Company (2011; filmed for television).

…in a 2003 production of Proof, David Auburn’s Pulitzer Prize-winning play about a mathematically gifted but troubled young woman. McKellar later provided the voice of a superhero in the animated TV series Young Justice (2010–13, 2019).

…Katherine in David Auburn’s play Proof. That year Parker also first appeared on the hit television drama The West Wing, as the women’s rights activist Amy Gardner; turning a one-episode role into a recurring character, she earned an Emmy Award nomination in 2002. She continued to earn accolades as the…