The Railway Children

A happy, comfortable upper middle-class home in Victorian London is disrupted one night when three children see their father usher two strangers into his study

After an argument he leaves with the strangers and doesn't return

The children and their mother fall on hard times and move to a cottage in the Yorkshire countryside

Fascinated by the nearby railroad, they wave to the passengers faithfully every day, and their vigilance and courage prevent an accident

And their kindness makes friends of some important people who can help solve the mystery of their missing father ...