Penelope Mitchell (born July 24, 1991) is an Australian actress, best known for playing the role of Letha Godfrey on the American horror television series Hemlock Grove and Liv Parker on The Vampire Diaries. She is a cousin of actress Radha Mitchell. Mitchell finished in the top one-percent of her graduating year, with an International Baccalaureate diploma. She attended Melbourne University, with the intention of becoming a lawyer. During her time there she continued to perform and wrote prolifically for various publications. Mitchell completed her undergraduate degree in Arts: Media Communication, before moving to Los Angeles to pursue acting.

She began acting a few years before she landed her role on Hemlock Grove, appearing on television shows.