James 'Jimmy' 'Shamrock' Ellison (real name: James Ellison Smith) (1910-1993) was the original trail partner to William Boyd in the early Hopalong Cassidy films, and was replaced in that series by Russell Hayden. Ellison was groomed to become a bigger name by both Paramount and RKO, but he was unable to fully make the transition to a star of A-features. During the 1940s and early 1950s, he wound up doing B westerns. You'll find more on Ellison in the 'Heroes' section on the Old Corral homepage.

Jimmy Ellison as Johnny Travers