Producers Distributing Corporation (PDC)

A mad scientist uses captured criminals as experiments for his study on "the criminal mind" aboard his private ship.

The story concentrates on a travelling medicine show maintained by Bobby Clark and his relatives Minerva Urecal, Earle Hodgins and Joyce Bryant. Their progress is impeded when Hodgins is framed on a robbery charge, but Clark uses his fancy lariat to hog-tie the genuine crooks.

A prison trustee rescues a despondent executioner from a bar-room brawl, and is blamed for the fight by a tabloid reporter who actually started it, and loses parole, becomes embittered, and gets blamed for murder of guard.

Marshal Tim Smith is sent to Rawhide to battle rustlers. When the outlaw gang attempts to kill the new Marshal, they get the wrong man. Tim puts his identification on the dead man and poses as a known outlaw. This gets him into the gang where he is given the job of posing as the new Marshal.

Larry O'Neil, a ship's cook, finds and befriends stowaway Lois Austin, who is a fugitive from a murder charge. The ship's captain, Klodel, also finds her and forces her to do his will as he has received a cablegram and knows she is hunted.