Bill Hader was raised in Tulsa, OK, the oldest of three children of a dance teacher mother and a blue collar father who dabbled occasionally as stand-up comedian on the side. There was always plenty of laughing at the Hader house, and the family's only boy was a big fan of comic books and a voracious movie watcher, making his own comedy shorts with friends while in high school. After a few years studying film at Scottsdale Community College in Arizona, Hader moved to Los Angeles to pursue a career in the film business and kept busy at a succession of low-level production jobs in film and television. At night, he hung around comedy theaters such as Second City, and performed with a four-man improv group. It was while performing a backyard show with Animals of the Future that Hader impressed party guest Megan Mullally, of "Will and Grace" (1998-2006) fame. She arranged an introduction with "Saturday Night Live" producer Lorne Michaels, and literally within a few months, Hader went from being a production assistant with no acting credits whatsoever to a sketch performer employed by the most sought after comedic institution on television.Hader debuted as a featured player on "SNL" in the fall of 2005 and quickly established himself as a world-class impressionist, building a sizable repertoire of recurring personalities and characters on the show, including a dead-on Vincent Price and the chain-smoking Italian talk show host, Vinny Vedecci. He was promoted to regular cast member in the fall of 2006, the same year he began to make inroads with his film career. He had a small role in that year's "You, Me and Dupree" (2006), a romantic comedy starring Kate Hudson and Owen Wilson that was embraced by moviegoers to the tune of over $130 million, but nailed by critics. Most importantly, Hader formed a friendship with "Dupree" cast mate Seth Rogen that led to Hader's being cast as an enabler cop in "Superbad" (2007), written by Rogen and Evan Goldberg and directed by Greg Mottola. Hader followed-up in another surprise hit, Judd Apatow's "Knocked Up" (2007), which starred Seth Rogen as a slacker who impregnates a rising young on-air journalist (Katherine Heigl). Ironically, Hader's role as an editor at Heigl's network was shot at the same office as the cable network E! where Hader had previously worked as an editor.Hader's third film appearance in 2007 was in the low-budget comedy "Hot Rod" (2007), featuring "SNL" star Andy Samberg as an aspiring stuntman and Hader as one of his supportive best friends. The rising comic actor returned to his Saturday night gig in the fall of 2007, where he continued to cultivate a fan base with his impressions and his appealing, offbeat characters often inspired by his love of obscure pop culture history. In the summer of 2008, Hader was again highly visible in a number of seasonal hits, beginning with "Tropic Thunder," a spoof of big budget war movies directed by Ben Stiller and starring Stiller, Jack Black and Robert Downey, Jr. Hader had a supporting turn as a scurrilous film studio executive. He followed this up with a small role in the Rogen-scripted stoner buddy comedy, "Pineapple Express" (2008). The biggest hit of the bunch that summer, however, was "Forgetting Sarah Marshall," a breezy romantic comedy starring Jason Segel as a devastated recent ex-boyfriend, who is convinced by his step-brother (Hader) that he needs a vacation to get away from his ex-girlfriend's memory.Making his mark as a behind-the-scenes talent as well, in 2008 Hader was tapped as a creative consultant on the long-running Comedy Central animated series, "South Park" (1997-), which earned an Emmy the following spring. He also co-wrote a web series entitled "The Line," about the escapades of science fiction fans who line up weeks in advance of an upcoming geekfest film opening, as well as appearances on Michael Cera's offbeat web comedy show and "Tim and Eric Awesome Show, Great Job" (Adult Swim 2007-2010). Hader returned to theaters in the spring of 2009 with "Adventureland," Mottola's well-received indie comedy about seasonal employees of an amusement park, in which he gave a charming performance as the venue's eccentric assistant manager.In quick succession, Hader went on to appear as General Custer in the family blockbuster "Night at the Museum: Battle of the Smithsonian" (2009) and lent his voice to the similarly huge animated hit, "Ice Age: Dawn of the Dinosaurs" (2009). He was bumped up to first billing in "Cloudy with a Chance of Meatballs" (2009), an CGI adaptation of the popular children's book in which Hader was cast as nerdy inventor Flint Lockwood, who unleashes a storm of problems when he creates a way to transform water into food. Filmmaker Mottola recruited Hader a third time for a supporting role in "Paul" (2010), a buddy comedy about two friends' (Simon Pegg, Nick Frost) pilgrimage to a science-fiction convention, before he and "SNL" alumni Amy Poehler teamed up to voice Hansel and Gretel in the animated film "Hoodwinked Too: Hood vs. Evil" (2010). Meanwhile, for the first time in his "SNL" career, Hader earned an Emmy Award nomination in 2012, getting the nod in the category of Outstanding Supporting Actor in a Comedy Series. The same year, he portrayed Andy Warhol in an amusing appearance in the alien-centric sequel "Men in Black 3" and later reprised his voice role as Flint in "Cloudy with a Chance of Meatballs 2" (2013). Mere months before the animated film's release, Hader announced that he was leaving "SNL," joining frequent co-star Kristen Wiig as a high-profile departure from the venerable comedy show. Hader's next big screen appearance came in Ned Benson's art house film "The Disappearance of Eleanor Rigby: Them" (2014), re-edited from a pair of films that examined a couple's breakup from each participant's perspective. Following a role in David Wain's romantic comedy parody "They Came Together" (2014), Hader garnered terrific notices opposite Wiig as despondent siblings in the drama "The Skeleton Twins" (2014). Hader next co-starred in two very different films, the Pixar comedy "Inside Out" (2015), in which he played the personification of Fear inside the brain of a young girl, and the Judd Apatow romantic comedy "Trainwreck" (2015), in which he played a sports-injury doctor who falls into a relationship with a reporter played by star and screenwriter Amy Schumer. He followed this with a reunion with fellow SNL vets Fred Armisen and Seth Meyers for the mockumentary series "Documentary Now!" (IFC 2015-), in which different classic documentaries were affectionately parodied.Hader next appeared in Rebecca Miller's romantic comedy "Maggie's Plan" (2015) before returning to voice work in the hits "Sausage Party" (2016), "The Angry Birds Movie" (2016) and "Finding Dory" (2016), as well as a credit as voice consultant for the endearing robot BB8 in "Star Wars: The Force Awakens" (2015). Hader expanded to motion capture work as The Bloodbottler in Steven Spielberg's fantasy "The BFG" (2016) and as Alpha 5 in "Power Rangers" (2017). Hader reteamed with longtime pals The Lonely Island for their mockumentary film "Popstar: Never Stop Never Stopping" (2016) before co-writing, directing and starring in the cable comedy "Barry" (HBO 2018-), the story of a hitman who becomes involved in the Los Angeles theater scene.