It's a half-term long weekend, and the Five arrange to meet up for a hike over the moors.
Timmy hurts himself by getting stuck down a rabbit hole, so Julian and George set off to find a vet leaving Dick and Anne to find a farmhouse for the night. The farmhouse they come across does not extend them a very warm welcome and
reluctantly allows Anne to sleep in an attic room. Dick,
meanwhile, has to make do with a corner in the barn!
During the night, Dick is woken by a sinister man calling his name. Dick isn't too sure whether or not he is dreaming when the man gives him a very strange message! "Two tree, Gloomy Water, Saucy Jane and Maggie knows!"
In the light of day, and when the Five meet back up, Dick's late night encounter seems bizarre - to say the least.
However, they discover there is a lake called "Gloomy Water" and on it stands a derelict house called "Two Trees." They decide to make their way there and set up camp. They could also see if there was anything in Dick's strange message!
Sunken in the lake, the discover a boat called "Saucy-Jane" and hidden in it they find stolen jewellery.
However, getting away would not be so easy when "Maggie" turns up along with a scruffy little man called "Dirty Dick" - obviously the "Dick" the mysterious message had been