X-link to the Mystery megathread for a discounted mystery/suspense thriller set in an alternate history, if you think you might be interested:
The Darkest Hour by Tony Schumacher, which is set in a 1946 after the Nazis have invaded Britain, where a British detective must now work with the SS, investigating crimes in the new regime, similar to Len Deighton's
SS-GB and Jo Walton's Small Change trilogy.