The second of Columbia Pictures' four "Wild Bill Saunders" westerns, Pioneers of the Frontier features William Elliott as the title character who discovers that his uncle Mort (Lafe McKee) has been murdered by an unscrupulous ranch foreman, Matt Brawley (Dick Curtis). But before he can right Brawley's wrongs, Wild Bill is arrested for a murder he didn't commit. Sidekick Cannonball Sims (Dub Taylor) and disgruntled girl rancher Joan Darcy (Dorothy Comingore) plot to break Wild Bill out of jail but Brawley is wise to their plan.