Mystery of the River Boat

George Lloyd

Heenan Elliott

Clancy Cooper

Robert Lowery

Steve Langtry

Ray Bennett

Jack Cheatham

Lyle Talbot

Rudolph Toller

Arthur Hohl

Clayton

Oscar O'Shea

Capt. Ethan Perrin

Anthony Warde

Bruno Bloch

Francis McDonald

Batiste

Eddy Waller

Charles Langtry

Marion Martin

Celeste Eltree [Chs. 1-4, 7]

Eddie Quillan

Jug Jenks [Chs. 1-4, 7]

Alec Craig

Chief Engineer [Chs. 1-4, 7]

Ian Wolfe

Hermann Einreich [Chs. 1-2]

Dick Curtis

Craig Cassard [Ch. 1]

Byron Foulger

Dr. Hartman [Ch. 1]

Earle Hodgins

Jean Duval [Ch. 5]

Cy Kendall

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

Jimmie Dodd

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

Mantan Moreland

Lewis D. Collins

Maurice Tombragel

Ande Lamb

Henry MacRae