A giant warship docks in Alexandria harbour and Macky learns from Portia that the ship’s mission is to attack the rebels resisting the Romans in Galilee. Macky inspires his neighbour, the young genius Sollie, with the story of David and Goliath. Sollie comes up with a plan to sink the ship.

When Macky and Samuel are captured and imprisoned on the doomed ship, the story of how God released Peter from prison encourages them never to give up hope. As a result of the heroic destruction of the ship, its Roman architect decides to stay away from objects of war.