From book cover: Holly's foot slipped on the roof of the barge. She felt herself falling, helpless. Then she felt the impact as she plunged into the deep, turbulent water. Darkness closed over her head. A restful week on a barge should keep Holly, Tracy and Belinda - The Mystery Club - out of trouble. Until they offer a lift to an injured girl. The Mystery Club soon discovers that the strange is not what she seems...