Three Go Back is one of the classic novels of prehistoric life, along with such works as Jack London's Before Adam and William Golding's The Inheritors (which reverses the roles that Mitchell allots to Cro-Magnon and Neanderthal Man). It is a lyrical idealization celebrating the possibility of a free, fulfilling and uncomplicated existence. It was written in a mood of deep disenchantment which many people in Britain felt in the years after the Great War, but it has its own kind of passionate optimism: a hope that the corruptions afflicting the human spirit (no matter what their origin might be) can be set aside. It is not difficult, even today, to sympathise.