Railroad detective Matt Clark solves mysteries with his assistant.

Matt teams with Pat Garrett after a large herd of horses is stolen.

Matt and Frankie go to Kansas City to aid in the capture of outlaw brothers Frank and Jesse James.

When the Apache chief leads a raid on a train depot, looking for weapons and provisions, one of his braves is captured.

Despite their position undercover as members of the infamous Quantrill gang, Matt and Frankie cannot stop them from carrying out a vicious massacre in Lawrence, Kan.; Matt sets out to hunt down Quantrill for what happened.