There's nothing in the glorious summer day to suggest anything even remotely sinister. In fact, Alex Callahan, a news correspondent, surprises himself by enjoying the Renaissance Faire that his six-year-old twins, Kevin and Sean, have dragged him to. The boys are delighted by the jugglers and magicians, jesters and food mongers dressed in full Elizabethan costume. But it's the joust that the boys have really been waiting to see. Alex sits in the amphitheatre, watching the joust while keeping half an eye on the twins, who have clamoured to join the children assembled to cheer on the Green Knight. After watching the Green Knight despatch the Black Knight, he turns to see how the boys have enjoyed the joust, but at first he can't see them. And then: he really can't see them at all. The perfect day has turned into to a nightmare. There's no sign of Sean and Kevin, and eventually the police arrive. They're initially suspicious of Alex - after all, it's common knowledge that most children are abducted by their fathers - but no one can explain the small origami figure he finds after he returns to his empty house. Or the bowl of water that has been left on the top shelf of the wardrobe. Or