Agents of a foreign power are seeking to get possession of the plans of a new aeroplane motor invented by Dick Benton. Under cover of darkness they succeed in their scheme and are escaping in their automobile when it plunges over an embankment near Lone Point.
Rupert Winslow, traffic superintendent of the railroad that employs Helen as operator at Lone Point, receives a telegram stating that his wife, who is ill, will be on the midnight express. He calls in Summers, a veteran brakeman on the passenger run and instructs him to watch over Mrs. Winslow and...
Helen, station agent and telegraph operator at Lone Point, is in despair over a broken sounder when Morley, who has dropped off a passing freight, offers to fix it for her. Recognizing in him a man whose skill points back to happier days, Helen encourages him to tell her his story, promising to get...
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,...
Their demand for money having gone unheeded, Garibaldi and his gang wreck Number One. Howard, who attempts to interfere, is battered into insensibility. The criminals then place a note in the man's pocket warning the railroad officials to heed their demands in the future.
A pair of crooks steal a valuable package, hold up the crew of a freight engine, and compel the engineer to aid their escape. Learning this, Helen climbs into the cab of a locomotive standing on a siding and takes up the chase.
A crooked mine owner attempts to hijack his rival's shipment of ore, but Helen foils his plot by jumping onto the engine and pulling the throttle wide open, eventually exposing the unscrupulous villain.
Helen, discharged by the superintendent without justification, comes to the rescue when a flat car, loaded with dynamite, is tearing to certain destruction down the grade, bearing the mischievous son of the superintendent.
Helen, the telegraph operator at Lone Point, receives a telegram for Sydney Wayne, superintendent of the Graham Gravel plant, advising him that the plant has changed ownership and that Stanton Grey accompanied by his daughter Edith, is on his way to Lone Point to inspect the property. Wayne is...
In a scuffle between the assistant foreman and a discharged employee at the mountain construction camp the latter's revolver is fired, bringing about a dynamite explosion that severely injures many of the men.
Trent returns to the throttle too soon after his recovery from illness. On the following day Ruth, his daughter, and Hume plan to elope. Trent, with a new fireman, is suddenly taken with a weak spell and when the fireman becomes panic-stricken there is a scuffle which ends with the fireman thrown...
When informed by Helen that the rival railroad proposes to cross the Salt Lake's tracks, McKay, Division Superintendent, rushes a guard of men to Lone Point. This temporarily blocks the rival road's plan, but only until its force of men has been strengthened.
King attempts to tighten the brake of a freight car standing near the summit of a steep grade at Lone Point. Suddenly, the brake chain snaps and the train commences to roll down hill. Helen sees King's peril, rides to a point just before a curve, crawls hand over hand across a rope which she has...
