Mysterious old solicitor Mr. Blunden visits Mrs. Allen and her young children in their squalid, tiny Camden Town flat and makes her an offer she cannot refuse. The family become the housekeepers to a derelict country mansion in the charge of the solicitors. One day the children meet the spirits of two other children who died in the mansion nearly a hundred years prior. The children prepare a magic potion that allows them to travel backwards in time to the era of the ghost children. Will the children be able to help their new friends and what will happen to them if they do?

Jimmy Riley makes friends with Colin and Brian Buxton, both keen members of a schoolboys' scramble club. Lennie and Cliff, old friends of Jimmy's, steal wealthy Mr Hepplewhite's car. Jimmy finds the crooks with the car but will not join in with them.

A female private detective, Harriet Zapper, is hired by a rich old man to find his missing children, and becomes involved in counterfeiting and murder.

Blinker, so named because he blinks whenever he has a bright idea for a new invention, is the son of an eccentric Professor who is developing a top secret Pulsar Crystal X. Blinker's inventions help him to be a successful goalkeeper and to keep an eye on The Masons gang - and some real crooks.