Ubik by Philip K. Dick
An accident has occurred. Joe Chip and his colleagues—all but one of them—have narrowly escaped an explosion at a moon base. Or is it the other way round? Did Joe and the others die, and did the one fatality, Glen Runciter, actually survive? If Glen is dead and Joe alive, why does Joe keep getting weird messages from Glen? Is Joe's experience of his post-accident life just a hallucination, played out as his flash-frozen body lies in suspended animation? Joe's reality begins to fall apart, and a mysterious, vaguely mystical substance called Ubik—available in a handy spray can—appears to be the only thing that can stabilize it. From the stuff of space opera, Dick spins a deeply unsettling existential horror story, a nightmare you'll never be sure you've woken up from.—L.G.