Young Tom Dawes is enthralled by the sight of a fine schonner sailing up the Avon Gorge. Soon he and his father become mixed up in the mystery of a missing girl, a half recorded message, and intruders at Bristol Docks...
The adventure continues as Sid Dawes finds the runaway girl, Lynn, and Tom learns more about the mysterious recorded message. Trouble is looming for them all: the villainous Colonel Gaines has become suspicious - and he's a dangerous enemy.
