The dedication of Sal Viscuso to the craft of acting can be dated to a singular evening in 1967. A college freshman, he happened upon a teleplay of Ronald Ribman's CBS Playhouse: The Final War of Olly Winter (1967) and was so inspired by Ivan Dixon's Emmy-winning rendition of the title role that he entered the drama department the very next day, later explaining, "I felt that there I had found my family." He earned his BA from the University of California at Davis, then went on to study with Olympia Dukakis at NYU School of the Arts, from which he graduated with an MFA.

Opportunities presented themselves rapidly, and Sal made his film debut in the classic The Taking of Pelham One Two Three (1974). An introduction to Burt Metcalfe, associate producer of the iconic series M*A*S*H (1972), led to his move to Los Angeles, and soon Sal was a regular on NBC's sitcom The Montefuscos (1975). He was an off-screen loudspeaker announcer (as well as various other characters) on M*A*S*H (1972); appeared in Gene Wilder's homage to 1920's Hollywood, The World's Greatest Lover (1977); improvised in Robert Altman's Three Women (1977); and played multiple parts on the beloved Barney Miller (1975) (one of which was written especially for him by the show's creator, Danny Arnold).