Just finished The Way Up is Death - written by Dan Hanks, published by Angry Robot Publishing ( you can purchase their books directly from their website).
The blurb: " When a mysterious tower appears in the skies over England, thirteen strangers are pulled from their lives to stand before it as a countdown begins. Above the doorway is one word: ASCEND. "
The thirteen soon discover it's a game, you have to work your way through each level of the tower before you can ascend to the next, but each level has a price that needs to be paid and what will they find at the top?
This could so easily have been just another adventure/ horror book being churned out but it turned out to be so much more, you end up really caring about the characters (or not) and the ending - even though you get to understand what is going to happen - is really well written. I thoroughly enjoyed reading this book and was genuinely sad to reach the end, I can see this will be one that I re-read many times to come. Can definitely recommend it!