It is 1997. The British government now runs island prison colonies to take dangerous offenders from its overcrowded mainland jails. Among all these colonies, Sert, 25 miles off the north Cornish coast, has the worst reputation. There are no warders. Satellite technology is used to keep the convicts under watch. New arrivals are dumped by helicopter and must learn to survive as best they can.

To Sert, one afternoon in July, is brought Anthony John Routledge, sentenced for a sex-murder he did not commit. Routledge knows he is here for ever. And he knows he must quickly forget the rules of civilized life.

But not all the islanders are savages. Under the charismatic leadership of one man a community has evolved. A community with harsh and unyielding rules, peopled by resourceful men for whom the hopeless dream of escape may not be so hopeless after all ...