Richard John Grieco Jr. (born March 23, 1965) is an American actor and former fashion model. He played Detective Dennis Booker in the popular Fox series 21 Jump Street (1988–89) and its spin-off Booker (1989–90). He has also starred in various films, including If Looks Could Kill and Mobsters (both 1991). He has voiced characters in several video games and appeared as either himself or his 21 Jump Street character in several films and television shows. Since 2009, he worked as a painter, working in a style he calls abstract emotionalism. Richard Grieco was born in Watertown, New York, the son of Richard and Carolyn (O'Reilly) Grieco. He is of Italian and Irish descent. Grieco worked as a model for Armani, Calvin Klein and Chanel. He played Rick Gardner on One Life to Live from 1985 to 1987. In 1988, Grieco began appearing as Detective Dennis Booker on the shows 21 Jump Street and its spinoff Booker. Grieco's feature film debut was as Michael Corben in If Looks Could Kill (1991) and has appeared in numerous films since then. Later in 1991, he played the young Jewish bootlegger and mobster Benjamin "Bugsy" Siegel in the film Mobsters. He also appeared in the TV series Marker in 1995. He played himself in the 1998 film A Night at the Roxbury as well as in an episode of the FX comedy It's Always Sunny in Philadelphia . Grieco began a singing career in 1994 with the Dunmire Band. He signed to a German label and released a CD, Waiting for the Sky to Fall, in 1995; he re-released the album in 2011, making it available on streaming services such as iTunes and Spotify. In 2004, he formed the band Wasteland Park with music manager Cheryl Bogart. In 2009, several years after being encouraged to do so by Dennis Hopper, Grieco publicly revealed that he has been painting since 1991 and sold his first painting for $10,900. He calls his work "Abstract Emotionalism."