Hugo Award: Best Novel nominee (1978).
RIDERS ON THE TIME STORM
The time storm had devastated the Earth, and all but a small fraction of humankind has vanished. In the rubble of the world, three survivors had formed an unlikely trio: Marc Despard, determined to find a way to stop the time storm; a leopard, dazed by the storm and following after Despard like a kitten; and a young woman with an unbreakable bond to the leopard.
Now, Marc searches relentlessly for a clue to the nature of the storm, not guessing that the time storm threatens not just the Earth but the entire universe – and that his two companions were the only hope of reversing the distortions in the fabric of the cosmos that were about to bring an end to all of space and time...