THE FOURTH MODE : <i> by N. P. Figgis (Penguin: $7.95, paper; 210 pp.) </i>

These days, though there are still plenty of ICBMs around, the novel of nuclear apocalypse seems oddly anachronistic. It seems to be what it describes: a dead end. This is too bad, in a way, because N. P. Figgis’ “The Fourth Mode” is one of the most interesting and poetic examples of the genre.

Figgis is vague about how the final war breaks out in the age of Bush and Gorbachev, but he excels in describing the reactions of the inhabitants, human, animal and even inanimate, of a small English town called Martinminster. Not only people are vanishing, he makes clear, but also nature, culture, God--everything. In “On the Beach,” Nevil Shute’s Australians awaited the end with resignation; in “The Fourth Mode,” with hours instead of months to prepare for annihilation, Figgis’ English experience a brief, intense flare-up of vitality, like the spurt of blood from a severed artery. They respond in diverse ways--loving, looting, killing--to the first crisis in history that makes all responses irrelevant.