Whispering Smith is a 1948 American Western film directed by Leslie Fenton and starring Alan Ladd as a railroad detective assigned to stop a gang of train robbers.

The supporting cast includes Robert Preston, Brenda Marshall and Donald Crisp.

He's glad to see Smith, who shoots Leroy and Gabby and is saved when a bullet is deflected by a harmonica in his pocket, given him long ago by his sweetheart Marian, who is now Sinclair's wife.

It saddens Smith to find out that Sinclair might be in cahoots with Barney Rebstock, a rancher with a bad reputation.

When Sinclair rides home, he finds Marian packing and strikes her, accusing her of leaving him for Smith.

The part of Murray Sinclair, Smith's friend who turns to crime, was supposedly inspired by Butch Cassidy.

[9][10] It included 2,000 feet (609.6 m) of railroad track, on which authentic 1870 locomotives owned by Paramount were operated.

[12] Sol Lesser, who had rights to ten Whispering Smith stories, wanted to film some of them with Robert Mitchum,[13] who had begun his career as a leading man in a pair of Zane Grey Westerns.