The Law of the 45's (also known as The Mysterious Mr. Sheffield in the United Kingdom) is a 1935 American Western film directed by John P. McCarthy.

[2] Though only two of the characters, Tucson and Stoney, appeared in this film, Williams would appear as the missing member "Lullaby" Joslyn in Powdersmoke Range shot in the same year for RKO.

Law of the 45s was made by Max's Normandy Pictures.

[3] Tucson Smith and Stoney Martin are driving a herd of cattle to sell when they come into saving Charlie Hayden from a gang of killers.

Tucson and Stoney sell their cattle to Hayden and agree to work for him, both as range hands and to stop the gang of killers hired from Mexico.