Besch appeared in a variety of television series, including Street Hawk, The Edge of Night, The Secret Storm, Love Is a Many Splendored Thing, Dallas, The Golden Girls, Murder, She Wrote, Somerset, Backstairs at the White House, It's Garry Shandling's Show, and Date with an Angel. She played Dr. Carol Marcus, the early love of Admiral James T. Kirk in Star Trek II: The Wrath of Khan (1982), and other films included roles in Victory at Entebbe (1976), The Pack (1977), The Promise (1979), Meteor (1979), The Beast Within (1982), The Lonely Lady (1983), The Day After (1983), Mrs. Delafield Wants to Marry (1986), He's My Girl (1987), Who's That Girl (1987), Steel Magnolias (1989), Tremors (1990), and Betsy's Wedding (1990).