Railroad detective Matt Clark solves mysteries with his assistant.

Frankie befriends an outlaw after his gang robs the train.

While investigating a train robbery, Matt Clark learns about Johnny Ringo; Frankie gets a job doing undercover work; Matt tracks Johnny down.

Former deputies plan on robbing a gold shipment after their brother is killed.

Matt and Frankie head to Tombstone, Arizona to track down Doc Holliday who they suspect is involved with the Clanton gang; while there, they meet famed sheriff Wyatt Earp and become part of the gunfight at the O.K. Corral.