Sam Rockwell (born November 5, 1968) is an American actor. He is known for appearing in independent films and also as a character actor portraying a wide variety of roles both comedic and dramatic in films such as Lawn Dogs (1997), The Green Mile (1999), Galaxy Quest (1999), Confessions of a Dangerous Mind (2002), Matchstick Men (2003), The Hitchhiker's Guide to the Galaxy (2005), Moon (2009), Frost/Nixon (2008), Iron Man 2 (2010), Conviction (2010), Cowboys & Aliens (2011), Seven Psychopaths (2012), The Way, Way Back (2013), Three Billboards Outside Ebbing, Missouri (2017), Vice (2018), Jojo Rabbit (2019), Richard Jewell (2019), and The Best of Enemies (2019).
Rockwell won the Academy Award for Best Supporting Actor for Martin McDonagh's Three Billboards Outside Ebbing, Missouri (2017). and was nominated the following year for portraying George W. Bush in Adam McKay's Vice (2018). In 2019, he portrayed Bob Fosse in the FX biographical miniseries Fosse/Verdon, earning him a nomination for the Primetime Emmy Award for Outstanding Lead Actor in a Limited Series or Movie. In 2022 he received his first Tony Award nomination for Best Actor in a Play for his performance in the Broadway revival of David Mamet's American Buffalo. His other stage performances include Zoo Story (2001), A Behanding in Spokane (2010) and Fool for Love (2015).
Rockwell made his hosting debut on Saturday Night Live on January 13, 2018, the tenth episode and first show of 2018 of Season 43, with musical guest Halsey.