Z'Dar appeared in several films, including Hot Chili (1985), The Night Stalker (1987), Cherry 2000 (1987), The Killing Game (1988), and Grotesque (1988). Z'Dar's name became recognizable when he played Matt Cordell in 1988's Maniac Cop, a film about a back from the dead hero NYPD cop turned evil avenger who brutally murders people. Z'Dar reprised his role in the 1990 sequel and Badge of Silence (1993).

Robert Z'Dar appeared in more than 121 films and television episodes, with at least one film appearance per year in 27 of the last 29 years (missing only 1986 and 2001). He continued making at least one film every year despite a serious back injury he suffered in 2002 on a movie set. Two of Z'Dar's films, Soultaker (1992) and Future War (1997) appeared in season 10 of Mystery Science Theater 3000, increasing his renown somewhat.

It was perhaps Z'Dar's performance in Maniac Cop that landed him the role of "Face" in 1989's Tango & Cash, alongside action stars Sylvester Stallone and Kurt Russell. He went on to appear in films such as The Final Sanction (1990), A Gnome Named Gnorm (1990), Killing American Style (1990), Beastmaster 2: Through the Portal of Time (1991), Mobsters (1991), Samurai Cop (1991), Return to Frogtown (1993), Marching Out of Time (1993), Death from Above (2011) and Easter Sunday (2014).

While appearing at Pensacon in Pensacola, Florida, Z'Dar was hospitalized for chest pains. He seemed to recover but subsequently went into cardiac arrest and died on March 30, 2015 after a month at the hospital.