Things are not going well for Dragon Lord Beelzebub. He had chosen schoolboy John Lewis because he thought that the human child would have little chance of finding Excalibur.

Beelzebub is amazed that, in a twinkling of an eye, John Lewis has changed into a young magician. He watches as the mysterious forces attract John back to the standing stones to do more time travelling and this time to just before the Roman Invasion of Britain.

This time John Lewis must save Boudicca, defeat an alien army and help his distant cousin Ursula Shipton begin a witches' coven that will protect the family's magical bloodline, (which created Excalibur), from the Romans.

Meanwhile, in modern Earth, the coven make plans to protect the young magician.