Dick Patterson, the “dude” engineer of the Midland, saves the superintendent’s daughter, Grace, and one of her chums from drowning when their boat capsizes on the lake that parallels the railroad. Helen, the operator at Lone Point, in answering Grace’s questions about her rescuer, lauds him to the skies. Dick accordingly receives an invitation to a lawn party to be given by Grace. Having been suspended for two weeks for some slight inattention to duty, he is at liberty to attend. On the day of the party, the Midland plans to run an important test train to clinch a big freight contract. Graves, business agent of a rival road, plans to delay the test train and thereby garner the contract. Graves, arriving early at the Cummings affair, calls one of his lieutenants aside and instructs him to see that the water tank near Lone Point is emptied. Grace overhears the plot and immediately ‘phones to Helen just as she is about to be relieved, so that she too can come over to the lawn fete. In the meantime Dick, dressed in his afternoon togs, is impressed into service to run the test train, the regular engineer having been taken sick. Helen, ever loyal to her road, rushes off to the water tank after receiving Grace’s message. There she is set upon by Graves’ hirelings and made a prisoner on top of the tank. Dick brings his train under the spout to take on water and assists Helen to the ground. In their hurry to get away the crooks have left their auto on the nearby road. Using it to good advantage, Helen and Dick overtake a special on the rival line and by a ruse they persuade the engineer and firemen to climb out of the cab. Without further ado, Dick takes a crossover switch and is soon proceeding on his test run with a “borrowed” engine.