Shadows On The Sage finds the 3 Mesquiteers answering the summons of Harry Holman the town drunk who was appointed sheriff on a dare. But like Charles Winninger in Destry Rides Again, he plans to bring in some deputies and we know who they are.
Tom Tyler, Bob Steele and Jimmie Dodd are the 3 Mesquiteers, but neither Holman or Steele know that Tucson Smith has a double riding with the outlaws who are in the control of banker Bryant Washburn who is trying to get a hold of Griff Barnet's mine. Including Bob Steele's twin.
This was a close run thing, but Holman turns out to be not such a jerk in the end. And of course the 3 Mesquiteers clean things up and ride off into the sunset.