To prevent a three mile journey around the mountain the telegraph wires at the construction camp have been strung over the precipice from the station on the mountain top. The operator is discharged when the superintendent suspects him of treachery and Helen is transferred to the station. Later, after the former operator has enlisted the aid of crooked brokers to use his knowledge in ruining the value of the road's stock, he receives an opportunity to get revenge on the superintendent. A car loaded with lyddite has been shipped to the camp to aid in the construction work and while the superintendent is inspecting it the operator rolls the door shut and starts the car and engine off around the curve. Helen, from her post up on the mountain sees that a collision with the president's special is certain. She conceives a daring plan and grasping a heavy length of chain climbs the telegraph pole and starts the long slide down the wires. The nerve gripping scenes end when she finally reaches the tracks and climbing out on a rope is just in time to drop to the top of the runaway car which is quickly brought to a stop.