Bobby (Roberta), Phyllis, and Peter lead us back in time to the year they were the Railway Children. When father mysteriously is called away and the family has to move from their mansion to a small cottage in the country, the children call upon their kind hearts and vivid imaginations to entertain them while mother is busy. They make friends with Perks, the Porter at the railway, and the Old Gentleman who waves from the 9:15 train every day. These three children save the day many a time, diverting trains from disaster, taking in Russian writers, and ultimately rescuing their father from his unjust imprisonment.