During Peter’s birthday party, strangers arrive and take Father away. Mother says he has gone away on business - but when will he return and what will Mother and the children do?
Now living in their new home in the country, without their father, the children befriend Perks at the local railway station and go ‘coalmining’ at the station stores.
Mother is taken ill and the children get a message of help to a kindly old gentleman on the train, who sends her a hamper.
Mother and the children come to the aid of a distressed Russian gentleman who arrives at the station and Bobbie learns the truth about her father.
Mother tells Bobbie she must keep her secret from the other children. Later, the children discover a fallen tree on the line as the express train is due.
The children are rewarded by the railway company, and they soon need their courage again when a boy goes missing in the tunnel.
The children save Jim from the tunnel and take him home to be looked after. A train arrives at the station bringing some good news.