Best known for his characterizations of two Philip Roth characters, in "Goodbye Columbus" (1969) and "Portnoy's Complaint" (1972), Benjamin had walk-on juvenile parts in some 1950s films and first earned adult recognition on Broadway, starring in Neil Simon's "Star-Spangled Girl" (1966). He had directed "Barefoot in the Park" in London the previous year. Other off-beat acting highlights include "Catch-22" (1970) and "The Sunshine Boys" (1975).