Children from two different groups stumble upon each other on a small island in a lake, sparking a rivalry as they compete to claim the land as their own. As they engage in a game of pirate-themed pretend, they're disrupted by the arrival of a mysterious stranger on a boat, forcing them to put aside their differences and work together to uncover his true intentions. But as they delve deeper, they may find themselves entangled in a much larger and more complex situation.

Swallows and Amazons
Four friends embark on a solo sailing trip to a secluded island in the Lake District, where they find themselves entangled in a thrilling conflict with rival kids. Meanwhile, a suspicious stranger on a houseboat mistakenly accuses them of a crime, adding an air of mystery to their journey.