Boyish-looking Peter Sarsgaard was born on March 7, 1971, at Scott Air Force Base, in Bellville, Illinois, to Judy Lea (Reinhardt) and John Dale Sarsgaard, an engineer who worked for the Air Force and later Monsanto and IBM. He is a graduate of St. Louis' Washington University, where he majored in history and literature.Initially trained with the Actors' Studio in New York, Peter began in comedy and became a co-founder of the comedy improvisational group Mama's Pot Roast. Such off-Broadway productions included Horton Foote's "Laura Dennis" and John Cameron Mitchell's "Kingdom of Earth."He made his screen debut in Tim Robbins' La dernière marche (1995) and was given more sizable roles in Desert Blue (1998) and L'homme au masque de fer (1998), as the ill-fated son of the Musketeer Athos, played by John Malkovich. Peter then started gracing the art-house circuit, making a violent, searing impression as a homophobic killer in Boys Don't Cry (1999) starring two-time Oscar-winner Hilary Swank as a trans-gendered teen.Other impressionable offbeat roles for Peter that have thrilled critics from coast to coast include Le mystificateur (2003), which earned him a slew of awards including the prestigious National Society of Film Critics Award. Prior to that, he showed off his versatility with portrayals ranging from a Russian nuclear reactor officer in K-19: Le piège des profondeurs (2002) to a drug addict in Salton Sea (2002). Other heralded performances include Garden State (2004) and, notably, Dr. Kinsey (2004).On TV, Peter appeared in recurring/regular roles in several critically applauded series and mini-series including The Killing (2011), The Slap (2015), Wormwood (2017) (as ill-fated Army scientist Frank Olson), The Looming Tower: aux origines du 11 septembre (2018) and Courir toute nue dans l'univers (2019). More recent films include Night and Day (2010), the villain in the DC Comics entry Green Lantern (2011), the Woody Allen drama Blue Jasmine (2013), Experimenter (2015), Jackie (2016) (as Bobby Kennedy), Les sept mercenaires (2016), Escobar (2017), The Sound of Silence (2019) and Human Capital (2019).In 2009, Sarsgaard married actress Maggie Gyllenhaal and have two children. He co-starred in the movie she wrote and directed -- The Lost Daughter (2021) starring Olivia Colman.