William Gregory Magnussen (born April 20, 1985) is an American actor and comedian of stage, television, and film. He is best known for roles in Into the Woods (2014), Birth of the Dragon (2016), Game Night (2018), Aladdin (2019) and No Time to Die (2020).
Magnussen was born in Woodhaven, Queens, New York, the son of Daina, an aerobics instructor, and Greg Magnussen, a professional bodybuilder and kickboxer. He has two younger brothers. His maternal grandparents were Lithuanian immigrants. He grew up in Queens around Woodhaven Boulevard until the age of 10, when he moved with his family to Cumming, Georgia. Magnussen graduated from South Forsyth High School in 2003, and later from the University of North Carolina School of the Arts.
Magnussen made his Broadway stage debut in 2007's The Ritz, starring Rosie Perez. In 2012, he was cast alongside David Hyde Pierce and Sigourney Weaver in Christopher Durang's Vanya and Sonia and Masha and Spike, premiering at the McCarter Theatre in Princeton, New Jersey, prior to its move to Lincoln Center in New York City. It then moved to the John Golden Theatre, where it was nominated for six Tony Awards. Magnussen was nominated for a Tony Award for Best Featured Actor in a Play for his role as Spike. In 2014, he starred Off-Broadway with Anna Gunn in a critically acclaimed production of Sex with Strangers directed by David Schwimmer at the Second Stage Theater.