Frank and Joe are elated to get hired to find an invention by an eccentric man who used to live on the outskirts of Bayport. But then their father comes up against a wall in his own case and recruits them for help. Juggling the two mysteries keeps the boys on their toes, but when a missing person's case comes knocking at their door, the boys have to race time to find the answers to all of them before it's too late.

Frank and Joe are hired by the bank manager to break up a counterfeit ring, only to find a plot deeper than they had imagined. Art by Maddy Moore (https://www.deviantart.com/livingalivecreator)

Frank and Joe Hardy get to solve their very first case without the help of their famous father, only for it to take a turn they never expected. (Cover image by LivingAliveCreator on Deviantart https://www.deviantart.com/livingalivecreator) (Components of The Tower Treasure and The House on the Cliff)

A girl runs away from home and it's up to Secret Seven to find her ! Jack's litter sister Susie is up to her usual tricks but she can't put Secret Seven off the trail of 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 see a house burn down, then they witness the theft of a valuable violin! Are the two incidents connected?

Dogs are disappering in the village where the Secret Seven live! But they are too busy quarreling to investigate! Then poor Scamper disappears...

There's a thief at Kirrin cottage! The Five - Julian, Dick, Anne, George and Timmy are determined to find out who

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.

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.