Hans & Konrad travel up to Sky Village, to stay with their cousin Anna and the boys tag along for a camping trip. However, it’s soon obvious that everything isn’t as it should be. Never one of my favourites, with this re-read, I’ve revised that opinion slightly - it’s well written, fast paced and has some nice interplay between the boys. However, the main mystery (not the title one) has such a preposterous explanation that it does feel very contrived, whilst the monster - obviously the big draw (title and artwork)- has only the most minor part to play. Not as bad as I remembered it, this is far from the worst TTI book and is worth a read.