Mr. Stoner is bad, and it seems his son is turning out just the same. Masked and dressed all in gray, Stoner's Boy moves like a ghost up and down the river, stealing and causing mischief. Seckatary Hawkins and his club have crossed this dangerous lad, and (to make matters worse) Briggen and the Pelham gang across the river won't leave the ruthless thief alone: They know that he's hidden his treasure hoard somewhere in his cliff cave lair, and they're dead set on having it for themselves. Still, it doesn't seem that anyone can stand up to this clever foe -- except maybe another newcomer in...