Crispin Hellion Glover (born April 20, 1964) is an American actor, filmmaker, and author. Glover is known for portraying eccentric characters on screen such as George McFly in Back to the Future (1985), Layne in River's Edge (1986), Rubin Farr in Rubin and Ed (1991), the "Thin Man" in the 2000 film adaptation of Charlie's Angels and its 2003 sequel, Bittleman in Like Mike (2002), Willard Stiles in the 2003 Willard remake, Grendel in Beowulf (2007), The Knave of Hearts in Tim Burton's Alice in Wonderland (2010), and as Phil in Hot Tub Time Machine (2010). He has collaborated with filmmakers such as David Lynch, John Boorman, Jerzy Skolimowski, Oliver Stone, Gus Van Sant, Dennis Hopper, Jim Jarmusch, and Miloš Forman.

In the late 1980s Glover started his company, Volcanic Eruptions, which issues his books and also serves as the production company of his self-produced art films, What Is It? (2005), It is Fine. Everything is Fine! (2007), and No! YOU'RE WRONG. or: Spooky Action at a Distance (2025). Glover tours with these films around the world and is currently in production on his fourth feature, filmed on sound stages at the property he owns in the Czech Republic.