Actor Scott Allan Campbell is a gifted character lead, skilled at portraying tough working-class characters. Born in Florida in 1959, he graduated from the University of West Virginia and made his small-screen acting debut in his mid-twenties. His early performances include appearances on episodes of such series as St. Elsewhere and 21 Jump Street, in such movies as In the Hands of the Enemy (1987), and in a handful of commercials. He has worked in period films, such as Ted Turner's Civil War drama Gettysburg (1993), and in genre vehicles such as The X-Files and Dark Skies. Audiences watching the FOX network's Boston Public will also have seen him in a prominent guest-starring role, but Campbell's most visible part since 1994 has been on NYPD Blue, where he has played the hard-nosed Detective Sergeant Martens of the Internal Affairs Bureau. Usually seen as an antagonist with a special resentment of Detective Andy Sipowicz (Dennis Franz), owing to the latter's early history of alcoholism, Martens originally was the relatively thankless role of a heavy in a series filled with anti-heroes. Beginning in the series' sixth season, with the episode "Show and Tell," however, Campbell's portrayal of Martens took on new dimensions as the writers added significantly to his depth. In that episode, Campbell gave as good as he got from Dennis Franz's Sipowicz, over what his character's job is and how he does it. From that episode onward, the sergeant from IAB (usually referred to informally as the "rat squad") has come off as more of a standup guy with an unpleasant job than a resident heavy. In 2002, Campbell also took on a small role in the high-profile drama White Oleander.