Five Go Off to Camp: The Famous Five investigate spook trains in the dead of night. The trains seem to vanish into thin air, but where do they go? The Five discover an unusual underground tunnel system and a secret train-service. If they follow the tracks, will they solve the mystery? Five Go to Billycock Hill: It's holiday time at Billycock Hill and the Famous Five make new friend - a real pilot! But when he disappears with top secret equipment, the Five begin to wonder if their new friend could be a spy.

The Secret Seven have a brand new meeting place but somebody else has been using it too. How dare they? Whoever it is is going there at night, and the gang are going to put a stop to it! They are determined to catch the cheeky intruder, whatever it takes. When Peter and Jack go looking for their lost model aeroplane in an old abandoned house, they find a lit fire in one of the rooms. So who is living there, and why? Looks like the Secret Seven have another interesting case to solve.

Julian, Dick and Anne are spending the holidays with their tomboy cousin George and her dog, Timothy. One day, George takes them to explore nearby Kirrin Island, with its rocky little coast and old ruined castle on the top. Over on the island, they make a thrilling discovery, which leads them deep into the dungeons of Kirrin Castle on a dangerous adventure. Who - and what - will they find there?

Five Have a Mystery to Solve: The Famous Five visit Whispering Island, another mysterious place with a million stories surrounding it. Is it really haunted? It's all fun and games until the Five get stranded there and realise they're not the only ones on the island. Five Go Down to the Sea: Somebody is flashing lights from the top of the old tower on the treacherous rocks off the Cornish coast. The Famous Five sense danger. But can they solve this mystery without getting hurt themselves.

When a sinister-looking man gets George in trouble with the police, the Secret Seven are outraged! Spying on him, the gang are certain hes bad news, but what exactly is he up to? They need to investigate, and solve the mystery, once and for all. Peter and Janet are the only witnesses when a car is stolen! They saw the thieves, and now the whole of the Secret Seven are involved. But when they realise theyre on the trail of a dangerous gang, the Seven dont feel quite so brave. Have they taken on too much this time?