A young scientist’s experiment goes awry when he creates a monster from a radioactive isotope and finds that the creature consumes energy to grow in size and terrorize the nearby town.

Successful movie director John L. Sullivan, convinced he won’t be able to film his ambitious masterpiece until he has suffered, dons a hobo disguise and sets off on a journey, aiming to “know trouble” first-hand. When all he finds is a train ride back to Hollywood and a beautiful blonde companion, he redoubles his efforts, managing to land himself in more trouble than he bargained for when he loses his memory and ends up a prisoner on a chain gang.

Phoebe Titus is a tough, swaggering pioneer woman, but her ways become decidedly more feminine when she falls for California bound Peter Muncie. But Peter won’t be distracted from his journey and Phoebe is left alone and plenty busy with villains Jefferson Carteret and Lazarus Ward plotting at every turn to destroy her freighting company. She has not seen the last of Peter, however.