Mystery of the Riverboat

Robert Lowery

as Steve Langtry

Marjorie Clements

as Jenny Perrin

Lyle Talbot

as Rudolph Toller

Arthur Hohl

as Clayton

Oscar O'Shea

as Capt. Ethan Perrin

Joe Devlin

as Louis Schaber

Anthony Warde

as Bruno Bloch

Francis McDonald

as Batiste

Eddy Waller

as Charles Langtry

Marion Martin

as Celeste Eltree [Chs. 1-4, 7]

Eddie Quillan

as Jug Jenks [Chs. 1-4, 7]

Alec Craig

as Chief Engineer [Chs. 1-4, 7]

Ian Wolfe

as Hermann Einreich [Chs. 1-2]

Dick Curtis

as Craig Cassard [Ch. 1]

Byron Foulger

as Dr. Hartman [Ch. 1]

Earle Hodgins

as Jean Duval [Ch. 5]

Cy Kendall

as Police Chief F. E. Dumont [Chs. 6-8, 11]

Ralph Sanford

as Sawyer, the garage owner [Chs. 5, 10]

Jimmie Dodd

as The Singer-Guitarist [Chs. 1-3, 13]