Elizabeth Anne "Lizzy" Caplan (born June 30, 1982) is an American actress. In film, she is best known for her appearances in Mean Girls, Cloverfield, Hot Tub Time Machine, Bachelorette, Related, True Blood, Party Down and in Masters of Sex.

Caplan provided the voice of the woman that argues with Glenn Quagmire in "Chick Cancer", and inspires Stewie Griffin to treat his girlfriend Olivia Fuller badly.

Lizzy, as her character of Virginia Johnson in Masters of Sex, appears in "Gronkowsbees" as the guys watch a show called the Bone Zone. The show features just the sex scenes from television, without the stories. The show notes that Lizzy is hooked up to electrodes and is about to have sex with a "guy who sounds American, but probably isn't."