He played several supporting parts while at Fox, acting the role of a junior law partner in the Clifton Webb comedy Sitting Pretty (1948) as well as a navy pilot in Slattery's Hurricane (1949).

A year later he returned to the small screen as gunslinger Matt Reardon, in "The Empty Gun" episode of the ABC/Warners Western series, Cheyenne, starring Clint Walker.

In 1958, Russell was cast in his best-known role: the stolid, taciturn Marshal Dan Troop, the lead character in Lawman, an ABC/Warners hit Western series that ran for four years.

Co-starring alongside Peter Brown, who played Deputy Johnny McKay, and Peggie Castle as Birdcage Saloon owner Lily Merrill, Russell portrayed a US frontier peace officer mentoring his younger compatriot.

Russell also appeared in other motion pictures for Warner Bros., notably as a Sioux chieftain in Yellowstone Kelly (1959), as well as a rich, corrupt cattle rancher, Nathan Burdette, in the highly successful Howard Hawks Western Rio Bravo (1959), starring John Wayne.

He replaced James Doohan, who had played the commander in the previous season, but left to start working on Star Trek: The Motion Picture (1979).