Jamie and Lucy have an encounter with what appears to be a pair of ghost children. But these spooky kids, Sara and Georgie, aren’t actually ghosts. They’ve travelled forwards in time to seek help, believing they’re going to be murdered by the wicked Mr and Mrs Wickens. And Lucy and Jamie’s strange visitor seems to be the key to it all. With his help, they must travel back to 1821 to save Sara and Georgie and redeem their remorseful new friend, The Amazing Mr Blunden.