The actor was born into a show business family that, along with his brother and father included his actress mother, Eileen Ryan, and his younger brother, singer-songwriter Michael Penn. After making and appearing in amateur films as a young teen, Penn made his feature acting debut in Francis Ford Coppola's "Rumble Fish" (1983) as a rowdy member of Matt Dillon's clique, and throughout his career delivered some unforgettable performances: he was the awkward fellow taught to dance by Kevin Bacon in "Footloose" (1984), the brother of Sean Penn in "At Close Range" (1986), and had perhaps his most memorable turn in a role that was alternately funnt and disturbing playing Nice Guy Eddie Cabot, one of the organizers of the botched heist, in writer-director Quentin Tarantino's breakthrough film"Reservoir Dogs" (1992). He would also have a fine turn as a dogged detective pursuing a star-crossed couple in the Tarantino-penned "True Romance" (1993), and was part of the powerhouse acting ensemble assembled for director Robert Altman's multicharacter film "Short Cuts" (1993).
Penn was also the recovering substance abuser-cum-screenwriter son of Danny Aiello in Paul Mazursky's satire of modern filmmaking, "The Pickle" (1993). His other credits of that era include "The Wild Life" (1983), Clint Eastwood's "Pale Rider" (1985), "Mobsters" (1991), "Best of the Best" (1989) and "Best of the Best II" (1993). Penn had the showy role of a homophobic cop in "Too Wong Foo, Thanks for Everything! Julie Newmar" (1995), was the youngest member of the Hat Squad in Lee Tamahori's "Mulholland Falls," co-starred in Abel Ferrara's Mafia drama "The Funeral" and appeared in the CBS miniseries adaptation of author Larry McMurtry's Western "Dead Man's Walk" (all 1996).
The actor grew increasingly hefty in subsequent years but never failed to find work in a diverse array of projects, ranging from action-comedies like "Rush Hour" (1998), goofy satires like "Corky Romano" (2001), thrillers like "Murder by Numbers" (2002), oblique indie mysteries like "Shelter Island" (2003), spoofs of classic TV series like "Starsky & Hutch" (2004)--Penn's father Leo directed episodes of the original 70s series--and stylish neo-noirs like "After the Sunset" (2004). Penn also amassed an impressive resume on the small screen, appearing on episodes of "Seinfeld," "Chicago Hope," "CSI: Miami," "Will & Grace," "Everwood" and "Entourage," and he starred with Randy Quaid and John Carroll Lynch as the titular siblings in the short-lived CBS drama "The Brotherhood of Poland, New Hampshire" (2003). Audiences who had grown fond of Penn's bearish presence were stunned to learn of his unexpected death at age 40 in 2006.