Brett Clifford Gelman is an American actor and comedian. He was born on October 6, 1976, in Highland Park, Illinois. He is best known for his roles as Murray Bauman in the Netflix series Stranger Things and Martin on the BBC series Fleabag.

Gelman began his career as a comedian in the early 2000s. He performed in numerous comedy clubs and improv theaters in New York City. In 2009, he was a writer and performer on the sketch comedy series Eagleheart. He also had a recurring role on the comedy series Another Period.