During a siege, a castle's scalder gives his son a reassuring introduction to the family trade. He explains the craft, encourages the boy to find his own calling and offers safety advice that a nearby rock thrower ignores. Even a disastrous family memory becomes a lesson in professional development. The pair wait for the attackers to gather before emptying their cauldron, but an enemy archer soon demonstrates that the other side has its own father-and-son apprenticeship.