In 'Endgame', God and the Devil wager the Earth in a bet, and it falls on an average English family to ensure that the world isn't plunged into World War 3.
I found this book to be a nice, everyday diversion, which sits squarely in the middle of the quality spectrum of books. For a comedy, I didn't find it particularly funny, but the plot was full of action and it was easy to read.
However, it really fell down on character development. The main character, Martin, is not very likable, and remains unlikable throughout the whole story - and he was the most developed character in the book! It really annoyed me how he treated his parents-in-law like scum for no justifiable reason, and assaulted his coworker (who hadn't done anything wrong) and got away with it. I was also annoyed at the highly derogatory tone employed towards many of the other characters such as the parents-in-law and gamer geek Henry, who was portrayed as a sad and deranged loser throughout the whole book despite the fact that he did more to help save the world than Martin did.
The other thing that disappointed me was the fact that the characters were overwhelmingly male, and the few females there were didn't get to do much except nag the men and slap people on the cheek - oh, or be rescued by the brave hero (the dislikable Martin) and fall head over heels in love with him for no other reason than that he saved their life. It's hard to get any more stereotypical and one-dimensional than that.
So overall, not a bad book, but not one I'd read a second time.