King and Chizmar join forces again with a powerful stand-alone novel that is also the final chapter in the Gwendy trilogy. When Gwendy Peterson was twelve, a stranger named Richard Farris gave her a mysterious box for safekeeping. It offered treats and vintage coins, but it was dangerous.

Pushing any of its seven coloured buttons promised death and destruction. Years later, the button box re-entered Gwendy's life. A successful novelist and a rising political star, she was once more forced to deal with the temptations that the box represented - an amazing sense of wellbeing, balanced by a terrifyingly dark urge towards disaster.

With the passing of time, the box has grown ever stronger and evil forces are striving to possess it. Once again, it is up to Gwendy Peterson, now a United States Senator battling the early symptoms of Alzheimer's Disease, to keep it from them. At all costs.

But where can you hide something from such powerful entities? Gwendy's Final Task is a wildly suspenseful and at the same time deeply moving novel in which 'horror giants' Stephen King and Richard Chizmar take us on a journey from Castle Rock to another famous cursed Maine city to the MF-1 space station, where Gwendy must execute a secret mission to save the world. And, maybe, all worlds.