This, the seventh book of the series, sees the Five delighted at being allowed to go on a camping holiday by themselves.
Due to the hair-raising adventure they had had the year
before, it had been decided that they would be accompanied by a responsible adult. To their amusement, the "responsible adult" turns out to be Mr Luffy, a teacher from Julian and
Dick's school, who is probably the most absent minded
person they know!
The holiday starts fine and Mr Luffy leaves the Five pretty much to their own devices (but still manages to keep a
watchful eye on them!) They make friends with a local
farm-boy, Jock, who lives with his mother and step-father.
The Five hear stories about a mysterious "spook train" that runs at night on a long deserted line then disappears into thin air! Not being able to resist the prospect of another
adventure they decide to investigate. They can hardly believe their eyes when the "spook train" actually turns out to exist and they see it for themselves.
With the help of their new friend, Jock, the Five set out to solve the mystery once and for all, and in doing so uncover a ruthless gang of black-marketeers who will stop at nothing to safeguard their secret!