London is wrecked by an atom war. Dr. Robert Elman skulks among the devestated ruins, as far as he knows the last human being left alive. His rifle is the one defence against the Pack - the wild, hunger-maddened dogs who persue him. At last, among the ruins of Trafalgar Square he finds one building more or less undamaged, St. Martins-in-the-Fields. Then starts the strange story of a fight to wrest some manner of life from the ruins, to get some hope for the future. In the midst of this he meets the possible last woman on earth.