When Kyle and Evie Preston start exploring the grounds of their late grandmother's house they discover an old, abandoned mine shaft and soon find that the old lady's stories about fairies trapped underground were true.

When Merlin cast a positive spell to protect the knights of the Round Table, he used ancient magic drawing on the power of Stonehenge, and the knights were put into a sort of suspended animation. The evil Morgana and her son Mordred were banished into another world for 1500 years, but a 20th-century scientist finds a gateway, and the dark lord has a vicious scheme to enslave King Arthur's world.