Ted Cassidy "Battlestar Galactica: The Complete Epic Series" [1978]), Cassidy can be heard providing temporary voice tracks of the Cylon Imperious Leader, before actor Patrick Macnee was contracted to voice the character. Other film work included his appearances in "Butch Cassidy and the Sundance Kid" (1969), "Mackenna's Gold" (1969), "The Limit" (1972), "Charcoal Black" (1972), "The Slams" (1973), "Thunder County" (1974), "Poor Pretty Eddie" (1975), "Harry and Walter Go to New York" (1976), "The Last Remake of Beau Geste" (1977) and "Goin' Coconuts" (1978). He also co-wrote the screenplay of 1973's "The Harrad Experiment", in which he made a brief appearance. In
Brian Cassidy of the Special Victims Unit, he lacks the emotional maturity to deal with sex crimes and the language to describe them. He views his partner, John Munch (Richard Belzer), as a mentor. Cassidy has a drunken one-night stand with fellow SVU Detective Olivia Benson (Mariska Hargitay), and expresses a desire to pursue a relationship. Benson turns him down, however, citing a policy of not having relationships with co-workers. Years later, Benson expresses regret at the way she handled the situation. This and the stress of the unit wear Cassidy down and, after an outburst in the squad room directed at