It was raining yet again and Peter was bored. Lucky enough to live in a large palace, he decides to explore some of the old quarters. There he finds a small door hidden behind a curtain that opens onto a realm beneath the palace. Finding himself shrunk to a fraction of his normal size, he enters the Enchanted Cavern, a magical place filled with animals, each with their own special ability. Peter embarks on a fantastic adventure that sees him making many wonderful friends, whom he leads in defence of their underground world from attack by an invading force.