John, Susan, Titty and Roger return to the lake for another summer camping on their island with their old allies, Nancy and Peggy, otherwise known as the Amazon pirates. But if they can't have the island, there's always Swallowdale, the secret valley, hidden from the world and containing an extra se...

John, Susan, Titty and Roger return to the lake for another summer camping on their island with their old allies, Nancy and Peggy, otherwise known as the Amazon pirates. But if they can't have the island, there's always Swallowdale, the secret valley, hidden from the world and containing an extra secret concealed within it.