Ranchers, with the help of Roy, raise money to build a reservoir but lose it to a gambler through a crooked stock deal. Songs include the title song, "Love Begins at Sunset on the Trail," "Lily of the Hillbilly Valley," "When Payday Rolls Around," and "Chant of the Wanderer."

On the night that radio singing star Roy Rogers and his band, The Sons of the Pioneers, are the guests of honor at a celebration welcoming them back to their hometown, the town bank is robbed. The local ranchers are furious, for the money was their share of construction costs for a dam being built by the government. Sheriff Sutherland, whose daughter Kay is in love with Roy, is resentful of Roy and tells him that if he had not come home and had the party, the thieves would not have been able to steal the money. Roy grows suspicious of Alison, a businessman who maintains a small ranch in the area, but whose main income is derived from a large casino in the next state. Roy tells the ranchers that they must sell all their cattle together in order to raise enough money to carry on with construction, but Alison offers to influence his casino partners to loan them the needed funds. Sutherland supports the idea, but Roy is set against it, as the partners will want all of the ranchers' stock in the dam as collateral. Soon after the meeting, Roy discovers that the car driven by Murdock, the construction camp foreman, has hubcap ornaments matching the one he found by the bank just after the robbery. Roy's friend, barber and newspaper publisher Gabby Whittaker, suspects that Alison and Murdock are working together, which in fact they are. Roy tells Gabby and the other townspeople that he and the band are going to El Paso for a radio broadcast, but they instead doubleback to Roy's ranch. There they steal some of Roy's horses, then Roy and Bob Nolan, one of The Sons of the Pioneers, go to the construction camp, where they confirm that Murdock's car was used in the robbery. Murdock and his men chase Roy, and although he escapes, the car is destroyed in a crash, thus ruining Roy's evidence. When Sutherland insists on going through with turning the stock over to Alison, Roy and the Pioneers abduct him and Kay, while Alison realizes that Roy must still be in town rather than El Paso. To continue the deception and gain time, Roy arranges for Gabby's daughter Sally to use her switchboard to patch into the El Paso radio station. Roy and the Pioneers give their broadcast, but Alison figures out the trick and all but Roy are captured when Alison frees Sutherland. After Sally and Gabby help Roy break the boys out of jail, they all go to Alison's casino, where Roy believes the stolen money is hidden. While the Pioneers take the place of the casino orchestra, Roy breaks up a meeting between Sutherland and Alison and takes back the ranchers' stock. Gabby sets off a smoke bomb, after which Sutherland and Roy see Alison retrieve the money. Alison and Murdock attempt to escape on horseback, but Roy quickly apprehends them. Soon after, the dam construction is resumed and Sutherland is put in charge of the water company. Roy is made the new sheriff and joins his friends on a hayride.