The Cave — Tim Krabbe

Respectable geologist Egon Wagter has always found the amoral Axel van de Graaf's charisma difficult to resist. But from their first meeting as adolescents on a field trip to Belgium, when three lives became inextricably linked in the caves of La Roche, he has never yet allowed himself to be drawn into his friend's criminal life. Instead he has kept his independence, preferring to learn about Axel's exploits as a drug baron from the papers. Now his life as a family man is in tatters and the escape route offered by an expedition to South America lacks only $40,000 to become a reality. So here he is, far from home in a South East Asian country where the penalty for running drugs is death, running drugs for Axel, but maybe also on the brink of finally understanding the secret of the cave and the love that might have been.