The success of Harry Potter has reinvigorated children's fantasy cinema and this lacklustre outing is just one of several attempts to cash in on the wizards and witches boom. Its pedigree is impressive, at least, being based on the second of British author Susan Cooper's five-book cycle of Arthurian fantasy novels about the battle between the forces of Light and Dark. This hurried, far-from-faithful adaptation follows American teen in England Will Stanton (Alexander Ludwig) as he discovers that he's the last of a group of immortal warriors, led by Merriman (Ian McShane) and Miss Greythorne (Frances Conroy). To defeat The Rider (Christopher Eccleston) and restore the power of Light, Will must hunt for six mythical signs scattered across time - but these journeys to the Viking era and beyond prioritise special effects at the expense of coherent plotting. David L Cunningham's showy direction leaves no overhead camera shot unused, while overindulging in the kind of rapid editing that may make children lose their Happy Meals.

A boy's life is turned upside down when he learns that he is the last of a group of immortal warriors who have dedicated their lives to fighting the forces of the dark.