The enormously high praise I've heard about this book almost spoiled it for me by setting my expectations impossibly high. Fortunately, it did a pretty good job of fulfilling them.
This is a short, frenetically paced, action packed novel that weaves in numerous characters and plot developments. It doesn't leave much room for dilly-dallying. Gulliver Foyle starts out as a rouge straight from the gutter who becomes emroiled in a quest for almost mindless vengence. In the process he becmes unwittingly entangled in an inter-planetary conflict and intrigue. We follow "Gully" as he undergoes a transformation, attains a new understanding of himself and humanity and mankind's potential.
In reading this I see how influencial it was, so many different elements I've encountered in the works of later writers. Imagine a cross between A. E. Van Vogt and Philip K Dick at their best and you will get an idea for the feel of this book. It also feels very ahead of it's time in many ways, exploring ideas and themes that became regular tropes later on. Some of the ideas being so far fetched that it blurs the line between SF and fantasy. It has dated very well.
Looking back, my review sounds exceedingly positive, why didn't I give it five stars? Personal reasons. His writing style jarred a bit with me at first. I struggled at times to understand the character's motivations. Minor criticisms really and they do not detract from the fact that this was a great, deeply ambitious book that I would recommend to almost anyone.