In "Trail West To Fury," the Maverick brothers and Dandy Jim Buckley wait out a flood. We learn why the brothers cannot return to their home town in Texas. They were framed for murders they did not commit. Bret and Bart became Indian fighters after the Civil War to stay out of prison. They are trail bosses on a cattle drive in this episode. I think the nature of the brothers' characters precluded the series from running longer than five seasons when Gunsmoke ran 20 and Bonanza 14. Bret and Bart were gamblers and while they were more interesting and more human than Matt Dillon, the Puritan TV audience would tolerate them only to a point. Roy Huggins' situational ethics ran its course.