A native of Minneapolis, MN, Vincent Kartheiser made a name for himself in the late '90s by choosing unlikely fare for an actor who, at the time, had just earned the right to drink legally. Making his screen debut in a bit role in the 1993 tearjerker Untamed Heart, opposite Marisa Tomei and Christian Slater, the blue-eyed, brown-haired Kartheiser subsequently found himself being cast in family fare, most memorably the action-adventure drama Alaska, in which he starred opposite Thora Birch and Charlton Heston (whose son directed the film). The film led to the leading role in the kiddie tech thriller Masterminds, which featured the young actor as a whiz kid who takes on an evil private-school headmaster, played by Patrick Stewart. Kartheiser's next role, however, would be his most defining in terms of establishing his range and presence. Tapped to play Bobby, a drug-addled, homeless street urchin in Larry Clark's Another Day in Paradise, a gritty look at the lives of a pseudo-family immersed in crime, Kartheiser rose to the challenge with a fearless, powerful performance, acting with such established pros as James Woods and Melanie Griffith. The film earned many accolades for the young actor, who then appeared in Strike! (later retitled All I Wanna Do), a barely released comedy set in a 1960s female boarding school. The film featured contemporaries Kirsten Dunst, Gaby Hoffmann, and Monica Keena, the last of whom was co-star of Kartheiser's next project, Crime & Punishment in Suburbia.
Screened at the 2000 Sundance Film Festival, Crime & Punishment in Suburbia was a moody, updated take on Dostoyevsky's Crime and Punishment, set in a modern high school. Kartheiser played Vincent, a reticent teenager obsessed with a girl (Keena) who is slowly going over the edge. The film furthered his reputation as a daring performer uninterested in taking the safe route, a path many actors of Kartheiser's generation followed for higher visibility. After a few little-seen films, Kartheiser next turned up on the supernatural comedy drama series Angel in 2002. In a truly original role, he played Connor, the miraculous human son of vampires Darla (Julie Benz) and the titular Angel (David Boreanaz). Thanks to being reared in an alternate hell dimention, Connor had more than a few chips on his shoulder upon his return to L.A.; his adolescent angst and rebellion was one of the main focuses of the series' fourth season. Returning to film work, Kartheiser went on to star in the well-received coming-of-age drama Dandelion, which was shown at the 2004 Sundance Film Festival.
He was part of the cast of the crime drama Alpha Dogs in 2006. But, he landed his breakthrough part in 2007 when he was cast as Pete Campbell, a junior ad executive, on AMC's award-winning drama Mad Men. In 2011 he played the bad guy in the sci-fi thriller In Time and provided the voices for a pair of the characters in the Oscar winning animated feature Rango.