Dark Days by Derek Landy

He's dead. She's deadly. The bad guys don't stand a chance. The fourth book in the bestselling Skulduggery Pleasant series. Skulduggery is gone, sucked into a parallel dimension. There is no OFFICIAL plan to save him. But Valkyrie's never had much time for plans. `A thoroughly satisfying blend of humour, magic and adventure' Rick Riordan, author of the Percy Jackson series
Binding: Paperback / softback