Born Philip John Clapp, "P.J." was raised in Knoxville, TN, where his mother was a Sunday school teacher and his father, who sold tires, was known to encourage his son's early start in practical jokes. Among his earliest stunts, he faked a report card to show all F's when he actually had earned all A's, and spread false rumors of his own venereal disease. He moved to Hollywood after high school with ideas of becoming an actor, though he lasted less than a month at the Pasadena Academy of Dramatic Arts. Meanwhile, he began writing for skateboarding magazines like Blunt, Bikini, and Big Brother, where a favorite staff pastime was inventing elaborately dangerous and stupid stunts - such as Knoxville testing the dependability of a bulletproof vest by shooting himself with a .38. Magazine editor Jeff Tremaine convinced the daredevil to videotape some his antics, which were then released as the "Big Brother Video Trilogy" and became an underground cult hit. Word spread of Knoxville's weirdly intriguing stunts, and his gleefully stupid antics and in-your-face persona became the object of a bidding war between Comedy Central and MTV. In the end, MTV won out and "Jackass" - a series co-created by Knoxville, Tremaine and director Spike Jonze - was born.Despite stern and very clear warnings that no stunt performed on the show was intended for mimicking, some fans predictably attempted to reenact hazardous tricks involving moving cars and barbecues; making headlines with their injuries. "Jackass" came under fire from parents' groups and the like, though it was Knoxville himself who pulled the plug in the fall of 2001, explaining "with this type of comedy, people become inured to the shock value after a while." The attention-grabber had no plans to slip out of the spotlight, however, and segued into a run of character and supporting roles on film. In 2001, Knoxville played opposite Sarah Jessica Parker as her doomed and unfaithful boyfriend in the direct-to-video release "Life Without Dick." The following year, he was tapped for a number of films, starting with a role as a bumbling ex-con in the Dave Barry-based adaptation "Big Trouble" (2002). He showed surprising versatility with a role in the period drama "Deuces Wild" (2002) and was featured as an alien in the summer blockbuster "Men in Black 2."Knoxville had the opportunity to bring the persona that made him famous to the big screen in "Jackass: The Movie" (2002), a feature-length stunt blowout featuring Knoxville getting stitches in his head after being knocked unconscious. The film opened at number one at the box office, thanks to its ability to offer fans an opportunity to enjoy Knoxville and show regulars Bam Margera and Steve-O without any of the content restrictions of the former TV series. Knoxville returned to acting in the little-seen dark comedy "Grand Theft Parsons" (2003), an adaptation of the bizarre events surrounding the death of singer-songwriter Gram Parsons, in which Knoxville played Parsons' manager. He turned around to play Dwayne "The Rock" Johnson's recovering alcoholic sidekick in the remake of "Walking Tall" (2004), managing to elevate the underwritten role with his comic energy. After essaying a tow truck driver-cum-sexual healer in the John Waters comedy "A Dirty Shame" (2004), Knoxville was well-cast in "Lords of Dogtown" (2005), the fictionalized version of the rise of freestyle skating in 1970s Southern California, in which Knoxville played a pimp-like promoter who lures early skating star Tony Alva into the limelight.In a high-profile movie coup, Knoxville and Seann William Scott co-starred as a modern day incarnation of Luke and Bo Duke in "The Dukes of Hazzard" (2005), a juvenile but occasionally amusing effort that drew over $100 million in box office sales. Despite the winning performances by the two male leads, both actors were overshadowed by the hype surrounding the acting debut of Jessica Simpson - Knoxville, in particular, received more press than usual for his alleged romance with the singer than he did for his performance in the film. The stars, both married at the time, vehemently denied having a relationship. Having proven himself a bankable leading man, Knoxville was cast in the lead in "The Ringer" (2005), a moderately successful, low-brow comedy about a plot to "throw" the Special Olympics that found the actor masquerading in a wheel chair and falling in love with Katherine Heigl. Critics savaged the film, with most finding the subject matter truly tasteless.Knoxville proved charismatic enough to carry the title character in the low-budget comedy "Daltry Calhoun" (2005), but over the subsequent two years, Knoxville was back to his old tricks with the low-budget, highly profitable sequels "Jackass Number Two" (2006) in theaters and "Jackass 2.5" (2007), which featured previously unseen footage from the crew and was released directly to video following a Comedy Central premiere. Additionally, Knoxville made several guest voice appearances over the years on animated series like "King of the Hill" (Fox, 1997-2010) and "Family Guy" (Fox, 1999-2002, 2005-) before rolling out "Jackass 3D" in 2010. In June 2011, Knoxville and the entire "Jackass" family were devastated after one of their brethren, Ryan Dunn, died in a fiery car crash in West Chester, PA. For his part, their de facto leader attended Dunn's memorial in Pennsylvania, as well as wrote a touching blog to Dunn on the official "Jackass" website, sounding alternately grief-stricken for his buddy one moment, then angry at him for drinking and driving in the next. It was a side "Jackass" fans had never seen of the perpetually joking Knoxville.