The Trail Blazers (1940)

The Continental Telegraph Co. is putting a telegraph line to the town and the fort. They know that the telegraph is needed to stop the activities of the outlaws, but only the outlaws can see the importance of the telegraph. They steal the supply wagons form the boys, which leaves only enough supplies to run a 30 mile line between Fort Dodd and Fort Jackson. But the outlaws attack the camp, killing everyone including Tom and Emily. The boys get more money and a new engineer to build the line between the fort's. This time, they are not going to let the outlaws stop them and they will find the head outlaw.