At one time a clerk for Columbia Pictures, Henshaw quickly worked his way up to casting director and copped one of his first major executive posts in that area with Universal in the early 1960s. Holding a series of vice presidencies during the 60s, Henshaw moved into producing late in the decade, eventually returning to Universal in 1975 as vice president in charge of production. He later assumed increasingly senior positions during the 80s and 90s as head of production for Universal, Polygram, American International Pictures and the Cannon Entertainment Group. Over the course of his career Henshaw has overseen or contributed to the development of some 80 films, with specific producing credits on films including "Mischief" (1985), "Can't Buy Me Love" (1987), "Happy Together" (1989), "Harley Davidson and the Marlboro Man" (1991) and "Rescue Me" (1992).