Red River Valley (movie, 1941)

To bring water to their valley, ranchers have raised money to build a dam. When that money is stolen, Allison suggests the ranchers sell their stock to a friend of his thereby getting the money needed to complete the dam. Roy has a clue that Allison was involved in the robbery and is out to get control of the valley. So Roy and the boys try to delay the sale of the stock while they look for proof against Allison.