Brynn Horrocks is an American actor. She has appeared in the films, Dummy, BAB, The Lords of Salem, Apocalypse According to Doris, and the cult classic, Rock 'n' Roll High School Forever.

She received industry notice for her recurring role as Abigail Whitman, the fiercely cruel mother of Don Draper (Jon Hamm) on AMC's series, Mad Men and had a recurring role on the HBO mini-series Show Me a Hero alongside Catherine Keener and Alfred Molina.