Born Kalpen Suresh Modi in Montclair, NJ, Penn was raised a first generation Indian-American by his father, an engineer, and his mother, a chemist for a perfume company; both were Gujarati immigrants from India. Yearning to perform since he was a child - something his parents had hoped was a passing phase - the young aspiring actor attended the Fine and Performing Arts Specialized Learning Center in Farmingdale, where he learned acting, dance, movement and vocal training. His parents' dream of a life for their son geared more toward becoming a doctor or lawyer or some other respectable profession saw a glimmer of hope when he attended the University of California, Los Angeles as a sociology major, though he also double majored in film while performing in several school productions. With a resume full of school productions and community theater, he began the arduous process of submitting head shots and going on auditions. But response to his efforts was tepid at best. Recognizing the problem, his agent persuaded him to Anglicize his name, which Penn initially dismissed. He eventually relented and was surprised to see a drastic rise in auditions and callbacks.After appearing in episodes of "Sabrina, the Teenage Witch" (ABC/The WB, 1996-2003) and "Spin City" (ABC, 1996-2002), he made his feature film debut in "American Desi" (2001), in which he played the hip-hop obsessed roommate of a college student (Deep Katdare) from a traditional Indian family. In the meantime, his profile on television increased when he showed up in episodes of "Angel" (WB, 1999-2004), "Tru Calling" (Fox, 2003-05), "The Agency" (CBS, 2001-03) and "NYPD Blue" (ABC, 1993-2005). Penn next made the disparaging choice of playing the Indian exchange student, Taj Mahal, in "National Lampoon's Van Wilder" (2002). Originally uninterested in the part because of the character's name and thick Indian accent, Penn was convinced by his agent to take it anyway. But despite the promises of rampant sex, ample gross-outs and the star power of Ryan Reynolds and Tara Reid, "Van Wilder" received a critical drubbing and soon whimpered out of theaters. Nonetheless, it did prove to be a breakthrough for the young performer.In 2003, Penn scored roles in three theatrically released movies. He appeared in the Indian-made comedy, "Where's the Party Yaar?" and played a brash first generation Indian-American whose cousin arrives from India to attend his college, putting a crimp in his hard-partying style. After portraying an Arab who shows off a rocket-powered grenade launcher that he received as a Christmas gift in "Malibu's Most Wanted," he appeared in the mediocre and ultimately forgettable romantic comedy, "Love Don't Cost a Thing." On television, he was a medical student renting a room from the parents of a struggling actor (Anthony Anderson), who returns home to raise his eight-year-old son (Damani Roberts) in "All About the Andersons" (WB, 2003-04). Originally replacing actor Paul Bartholomew after the pilot episode, Penn himself was later replaced by Aimee Garcia.Penn's major break arrived in the form of his next movie, "Harold & Kumar Go to White Castle" (2004), a college-age comedy with plenty of sex and gross-out humor, but also possessing three-dimensional main characters who long for more than just tiny burgers after a few bong tokes. Penn and co-star John Cho played Ivy League-educated roommates who, after indulging in some Cannabis sativa, have a sudden craving for White Castle hamburgers. The quest for the mythical sandwiches becomes a wild journey of self-discovery, as the two underdogs learn more in one night than they ever did in college, thanks in part to a surprise run-in with a hitchhiking Neil Patrick Harris as himself. Though perfect for the part, Penn had to earn his spot despite meeting and impressing the screenwriters at a party. Producers scoured the country and beyond for the right Harold and Kumar in an extensive audition process. After several auditions over the course of three months, Penn landed the part and was thrilled to finally play a character devoid of the stereotypical trappings that had plagued earlier roles. The small-budget film was a surprise hit at the box office and went on to earn a widespread cult fan base.The exposure from "Harold and Kumar" allowed Penn to play more diverse roles in larger projects. He appeared in an episode of "Six Feet Under" (HBO, 2001-05) and was cast in a few Hollywood blockbusters, including the decade-late sequel, "Son of the Mask" (2005), with Jamie Kennedy, and the underwhelming romantic comedy "A Lot Like Love" (2005), both of which failed to spark much interest with critics and audiences. Meanwhile, Penn was cast as the genius lackey of Lex Luthor (Kevin Spacey) in the long-awaited cinematic return of the Man of Steel (Brandon Routh), "Superman Returns" (2006), a role that went largely unnoticed. Meanwhile, Penn starred in the sequel "National Lampoon's Van Wilder: The Rise of Taj" (2006), reviving his character to take center stage as Taj attends Oxford University to study and show the uptight student body how to have a good time. The project was an unmitigated bomb after failing to crack $5 million at the box office. Penn ventured into more dramatic territory with his next film, "The Namesake" (2007), in which he played the son of Indian immigrants whose search for his own unique identity might cause him to lose touch with his heritage. Though not a hit with audiences or critics, Penn did earn respect for his nuanced performance.Not leaving his frat house persona behind just yet, Penn also starred that year in "Epic Movie" (2007), a disastrous spoof-du-jour on hit Hollywood movies that many felt was better left unmade. Turning back to television, he had a recurring role as teenage terrorist Ahmed Amar during the sixth season of "24" (Fox, 2001-10). After appearing in the straight-to-DVD road comedy "Vegas Baby" (2008), he revived the perpetually stoned Kumar for "Harold & Kumar Escape from Guantanamo Bay" (2008), which focused on their breakout from the infamous detention camp after being mistaken for terrorists onboard an airplane. Though not as well-received as the original, the movie did feature a funny scene with Harold and Kumar sharing a cocaine-laced joint with President George W. Bush (James Adomian). Starting in season four, Penn joined the cast of the popular medical procedural, "House" (Fox, 2004-12), playing a sports medicine specialist who more often than not is enthusiastic about taking risks with the irascible Dr. House (Hugh Laurie). But during season five, his character committed suicide in order for Penn to take a real-life job working for President Barack Obama, for whom he spent two years campaigning tirelessly.Inspired by his grandparents, who had marched with Mahatma Gandhi during India's push for independence during the first half of the twentieth century, Penn entered into public service in 2009, working for the administration as the Associate Director of the White House Office of Public Engagement, where he focused on youth, arts and Asian-American and Pacific Islander communities. In order to devote himself fully to the cause, Penn put his acting career on indefinite hiatus while also returning to his original name, Kalpen Modi. Little over a year into President Obama's administration, however, Penn's representatives announced he would be leaving his post to appear in "A Very Harold and Kumar 3D Chriustmas" (2011) as his signature stoner character. Though the administration had little comment, Obama economic advisor Austan Goolsbee suggested to ABC News that money may have been a factor. After his stint in Washington, Penn returned to work as an actor, focusing primarily on television. After an arc playing a boyfriend of Robin Scherbatsky (Cobie Smulders) on the sitcom "How I Met Your Mother" (CBS 2005-2014), Penn spent a stint hosting the game show "The Big Brain Theory" (Discovery 2013). Along with co-starring in the sitcom "We Are Men" (CBS 2013-14) and comedy-drama "Battle Creek" (CBS 2015), Penn hosted the documentary series "The Big Picture with Kal Penn" (National Geographic 2015). The following year, he returned both to Washington and to prime time as co-star of the political action drama "Designated Survivor" (ABC 2016-).