A Maze of Murders — Roderic Jeffries

After a night of hard partying, four British tourists fall asleep on a pleasure boat off Mallorca. The next morning, however, three of them, Sheard, Kirsty, and Cara, slowly realize that the fourth, Lewis, is no longer there. Inspector Alvarez is disturbed by a phone call during his leisurely breakfast ordering him to find the missing man. As Alvarez quickly discovers, though, Lewis was no ordinary tourist. Even though his twentieth adventure takes him away from his beloved Mallorca to mainland Spain and to Paris, Alvarez still finds plenty of time for nips of brandy, long midday meals, and even a siesta or two, as he attacks this latest impossible crime with his usual sleepy and sun-soaked vigor.