This picture was based on an old time melodrama by Lincoln J. Carter. Pauline Starke stars as Katherine Keith, whose brother David (Harold Goodwin) is vamped by Lola Nichols (Evelyn Brent). Lola belongs to a gang of crooks who are planning to rob the bank where David works. When one of the gang kills a man, David is arrested for the crime. He is convicted of the murder and Katherine is determined to prove his innocence. She becomes a member of the gang so she can evidence showing that David is not guilty, later rushing to the state capitol to reach the governor in time to prevent his execution. Every step along the way, the gang tries to stop her. Somehow she manages to board the Arizona Express, where her sweetheart, Steve Butler, a mail clerk (David Butler), is working. The two of them manage to thwart the gang and they save Katherine's brother.