When Lieutenant Mallory is ordered to report immediately for duty in Honolulu, he persuades his fiancée, Marjorie Newton, a beautiful society debutante, to marry him immediately, enabling them to spend their honeymoon in the Islands. Mallory and Marjorie attempt without success to find a minister to marry them on such short notice, but, as they are about to part at the station, Mallory sees a minister getting aboard the train he is to take, and he and Marjorie quickly decide to be married on the train. Once underway, they cannot find the minister, though they discover that the bridal compartment has been reserved for them. To avoid sleeping together, they stage a terrible argument, and Mallory spends the night in the washroom. The following day, Mallory and Marjorie have a genuine misunderstanding over the attentions of a French girl to Mallory. After reconciliation, Mallory gets off the train at a village in which there is a minister's convention, but, before he can return to the train, it leaves without him. Mallory hires a plane to follow the train, sees that a bridge ahead of it is on fire, makes a daring transfer from the plane to the train, and alerts the engineer in time to avoid disaster. Mallory and Marjorie are finally married in San Francisco and catch a boat to Honolulu for their honeymoon.