It is the 22nd century and humanity has spread to nineteen planets scattered across the Galaxy. They are connected by spaceships using portals in "null-space", a little-understood phenomenon which permits instantaneous transits across interstellar distances. There is a catch, however; the portals are few and far between, and the routes to other planetary systems long and complicated, requiring hundreds or thousands of "jumps". What's worse, it is impossible to return by the same route; an entirely different series of jumps must be found. The paths through the portals have only been discovered by trial and error, through sending out countless automated probes of which only a tiny percentage return. So the discovery of routes to new, habitable planets is of critical importance to relieving population pressures.
The hero of 'Night Walk', Sam Tallon, is a research physicist turned secret agent sent to Emm Luther, a colonised planet which has broken away from Earth, to discover the co-ordinates of a new planet which the Lutherans have found. His attempts to escape with the information fail, and he is blinded before being sent to an escape-proof prison isolated by a vast swamp and guarded by automated guns firing heat-seeking missiles. There he meets with another blind prisoner, Logan Winfield, who has spent years trying to restore his vision by developing glasses fitted with micro-cameras and a system of direct stimulation of the optic nerves (prosthetics being banned by the Lutherans for religious reasons). Tallon brings his research skills to bear on the problem and, with the surprising assistance of a senior prison official, is able to solve them by abandoning the cameras and designing the glasses to tune in on and display whatever a nearby person or animal can see. With this aid, they are able to put into effect the escape plan which Winfield has devised. The rest of the story focuses on Tallon's efforts to escape back to Earth and his adventures (including romance) along the way.
This story was written forty years ago and it must be thirty since I last read it. Shaw is one of my favourite SF authors: from the 1960s until his death in the mid-1990s he wrote 26 novels plus a large number of short stories. Most of his novels were stand-alones, set in a wide variety of environments and with equally varied plots and themes. All were quite short by modern standards ('Night Walk' is only 140 pages), fast-paced and intelligently written, and he was a great story-teller; his books are hard to put down.
So how does 'Night Walk' stand up today? Very well indeed; it is as good a read as ever. Shaw is excellent at creating interesting environments and plot devices and exploring their implications. The parasitic glasses are a fascinating idea and Shaw has fun with their possibilities and limitations (tuning in on the vision of a man who is hunting him, for instance). I would have liked a little more attention given to the effects of the different types of vision that animals and birds can provide; some wasted opportunities here, I think (although possibly less was known about animal eyesight at the time). Despite the short length and fast pace, he even finds time to outline the socio-economic structure of Emm Luther, which has consequences for the plot. I was slightly surprised that, very close to the climax, Shaw slows the pace down by having Tallon wrestle for several pages with the advanced mathematics and physics needed to solve the problem of null-space, but it's still an excellent read with a satisfying conclusion.