By Adam Markovitz
December 10, 2008 at 10:33 PM EST

Some actors have a single defining role; others define themselves by playing many. Although he’ll likely best be remembered as Hill Street Blues’ Sgt. Stan Jablonski, Robert Prosky — who died at age 77 on Dec. 8 in Washington DC from complications from a heart procedure — brought to life hundreds of parts on stage and screen during a five-decade career. With grey hair and wooly eyebrows, Prosky was equally at ease playing kindly old men, like the TV station owner in Mrs. Doubtfire (1993), and slimy bureaucrats, like the corrupt judge in The Natural (1984).

Born Robert Joseph Porzuczek in 1930 to a working-class Philadelphia family, Prosky moonlighted as an actor while working at New York’s Federal Reserve Bank before taking to the stage full time as a member of Washington D.C.’s Arena Stage repertory. He made his movie debut at age 51 in Michael Mann’s Thief (1981), but never gave up the theater: His first Tony nomination came in 1984 for the role of salesman Shelly “The Machine” Levene in David Mamet’s Glengarry Glen Ross (a part that went to Jack Lemmon in the 1992 movie version). In the years that followed, he played supporting roles in Broadcast News (1987) and Dead Man Walking (1995), landed a recurring role on The Practice as an accused priest, and even managed to play dad to Kirstie Alley twice: first on Cheers, later on Veronica’s Closet. He’ll make his final screen appearance in the upcoming thriller The Skeptic, co-starring Tim Daly and Tom Arnold. Prosky is survived by his two sons, actors John Prosky (True Blood, My Own Worst Enemy) and Andy Prosky (John Adams).

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