This is a short SF novel penned in 1978. Despite its laconic style, it rolls along at quite a rate. Lots happens. Lots of it could have happened on Earth, but no, it all happens on a slightly strange planet light years away. And lots of it happens in the protagonist's mind, worrying down strands of plot into ever more unlikely scenarios, until the whole mystery is revealed a few pages from the end. 
   For mystery it is: the planet's 'crown jewels' have been stolen, for no apparent reason, and then people start to be bumped off, also for no apparent reason.
   It's entertaining enough, but no classic. If you can pick up a copy for 20p somewhere, it will pass the time on a train trip or flight; but don't expect anything Heinleinesqe.