The Halliwells are on holiday in Arthurian legend territory and it is not long before Piper stumbles across a Druid ritual with Niall - tall, broad-shouldered, with soulful dark eyes - at its centre. Niall amazes the sisters by telling them that the Druids have brought him into the twenty-first century in order to re-create an ancient ceremony and produce a child with phenomenal powers who would be totally in their control. Niall is desperate to get back to his own time and the sisters promise to help, but they are going to have to call on all their strength to outwit the Druids.