Brian Duffield (born November 5, 1985) is an American writer-director. He wrote and directed the 2023 sci-fi horror film No One Will Save You and the 2020 dark comedy coming-of-age film Spontaneous. His previous writing credits include Love and Monsters (2020), Underwater (2020), The Babysitter (2017) and Insurgent (2015). He is known for having multiple screenplays included in The Black List, including his scripts for Jane Got a Gun (2015) and Your Bridesmaid is a Bitch.