A mean looking man gets poor George into trouble with the police! Secret seven decide to spy on the man and discover that he is up to no good.

A visitor to their tree house put the Secret Seven on the trail of some thieves, but first they have to unravel some strange clues.

Jack's new telescope promised hours of fun until Susie claimed her half share. But old feuds were forgotten once Janet glimpsed strange happening at Toring Castle. Who was lurking in ruined tower and why were the residents of Jackdaws disturbed?

The Secret Seven have a fantastic new hiding place but someone else is using it at night and it's Jack's little sister Susie who helps them catch the intruder.