Mortal Instruments — John Malcolm

Johnny Barber is a coffee connoisseur. He is also a sharp businessman with South American connections - his lover, Katie is the wide of an extremely powerful and ruthless South American capitalist. When a machine that can detect a potentially fatal coffee fungus is stolen, Lawrence Edwards, an official from the Department of Trade and Industry, secretly recruits Barber's assistance in tracking down those responsible. Johnny's hunch that more is at stake than simple theft is chillingly realized when Edwards and his associate are found dead in suspicious circumstances. There is big money in the coffee industry and lives don't cost very much. It's a painful discovery and one that will take him into South America and the murky depths of the international business community where people play by different rules and nothing is quite as it seems...