William "Billy" Gregory Magnussen (April 20, 1985 in Queens, New York) is an American stage, film, and television actor of Lithuanian descent.
- As the World Turns (2008 — 2010) as Casey Hughes (VII)
- The Brass Teapot (2012) as Arnie
- CSI: Crime Scene Investigation (2012) as Det. Michael Crenshaw
- Boardwalk Empire (2012) as Roger McAllister
- The East (2013) as Porty McCabe
- Into the Woods (2014) as Rapunzel's Prince
- The Big Short (2015) as Mortgage Broker
- Bridge of Spies (2016) as Doug Forrester
- The People v. O. J. Simpson (2016) as Kato Kaelin
- Birth of the Dragon (2016) as Steve McKee
- Ingrid Goes West (2017) as Nicky Sloane
- Get Shorty (2017) as Nathan Hill
- Unbreakable Kimmy Schmidt (2017) as Russ Snyder
- Game Night (2018) as Ryan Huddle
- Maniac (2018) as Jed Milgrim / Grimsson
- Velvet Buzzsaw (2019) as Bryson
- Aladdin (2019) as Prince Anders
- Untitled Prince Anders spinoff (TBA)
- No Time to Die (2021) as Logan Ash
Tropes associated with Billy Magnussen:
- Mr. Fanservice
- Typecasting: Sometimes plays a Dumb Blonde or a strange fellow.
- What Could Have Been: He screen-tested for the part of Shazam! in the DC Extended Universe before the casting of Zachary Levi.