William Hall is an American actor, director, trainer and mask maker in San Francisco, California. He is the editor of The Playbook, Improv Games for Performers.

Hall first became involved in acting when he took a drama class while attending Maggie L. Walker High School in Richmond, Virginia. He went on to obtain a Bachelor of Fine Arts in Acting from Boston University, where he was classmates with Geena Davis. After graduation, Hall came to San Francisco to pursue theater.

He has appeared in film and television including The Right Stuff, Twisted, Howard the Duck and Midnight Caller. He was one of the Nazis in the final ark scene in Raiders of the Lost Ark.

Hall is one of the founding members of BATS Improv, an improvisational theatre, and the last remaining “OB” (original brother) of Fratelli Bologna.