Utah Wagon Train (1951)

Rancher Rex Allen receives a summons from his uncle an old time frontiersman that he is in trouble The uncle has been hired to lead a modernday band of adventurers on a wagon train retracing the route taken by their ancestors 100 years ago Before Rex can talk to his uncle the uncle is murdered and Rex sets out to find the killer and the motive by taking his uncles place as the leader of the wagon train