They don't call District Attorney John Wallace "Honest John" for nothing, given his reputation for putting high-profile criminals behind bars. All he needs is one more big case to ensure his election as the state's next governor - and big-shot politico Mark Crandall is going to give it to him on a silver platter. A mutilated corpse has been identified as mobster George Dickson. Now D. A. Wallace has the body, a motive (the insurance money), and a prime suspect (Dickson's estranged wife Sally). Despite misgivings about the evidence, which is purely circumstantial, Wallace wins the conviction. Sally gets 20 years to life in federal prison, and Wallace gets elected governor. Then Crandall drops a bombshell: He bought and paid for a witness to provide phony evidence against Sally Dickson. Crandall framed her, but Wallace convicted her. As Crandall sees it, he now owns Wallace. But "Honest John" drops a bombshell of his own: He grants Sally Dickson a full pardon, resigns the governorship, and convenes a grand jury to investigate a miscarriage of justice in which he was an unwitting - and now unwilling - participant. But Crandall's nefarious cohorts won't go down without a fight, and even Sally is bent on revenge.
Noted character actor Barton MacLane (1902-1969) was one of the most popular big-screen tough guys in the 1930s and 1940s, best known for his villainous portrayals. In Man of Courage, enjoys a rare, heroic leading role, and also earned story and screenplay credit. MacLane's real-life wife Charlotte Wynters appears as Dickson's mistress Joyce Griffith, and they enjoy some snappy banter in their scenes together.