The Famous Five meet up at Kirrin Station and learn Aunt Fanny and Uncle Quentin will be holidaying in Spain, leaving the Five at home with the household's cook, Joanna.

Jo knows that Red Tower is a man, a dangerous fellow who lives in a castle-like house on a cliff-top.

Jo eventually leads Julian and Dick to a cliff-top house, where George is captive in a tower.

In the tunnel they meet Red Tower, a giant of a man with flaming-red beard and with mad-man's eyes.

She and Julian, George, Dick and Timmy the dog manage to make a getaway by boat.