Atwood has created a bleak vision of the future in what she calls "science speculation" rather than science fiction. Two stories run side by side: Snowman, apparently the last human left on earth and his struggle to adapt to the end of civilisation, and the story of his life before the catastrophe. The two narratives are brought cleverly together at the end but you might spend the first half of the book struggling to make sense of it all. Don't worry it will all make horrifying sense in the end - it does for Snowman.
Out of habit he looks at his watch - stainless-steel case, burnished aluminium band, still shiny although it no longer works. He wears it now as his only talisman. A blank face is what it shows him: zero hour. It causes a jolt of terror to run through him, the absence of official time. Nobody nowhere knows what time it is.