David and Jo Henniger, a doctor and children’s book author, in search of an escape from their less than happy lives in London, accept the invitation of their old friends Richard and Dally to attend their annual bacchanal at their home deep in the Moroccan desert – a ksar they have acquired and renovated into a luxurious retreat. On the way, the Hennigers stop for lunch, and the bad-tempered David can’t resist consuming most of a bottle of wine. Back on the road, darkness has descended, David is groggy, and the directions to the ksar are vague. Suddenly, two young men spring from the roadside, apparently attempting to interest passing drivers in the fossils they have for sale. Panicked, David swerves toward the two, leaving one dead on the road and the other running into the hills.
At the ksar, the festivities have begun: Richard and Dally’s international friends sit down to a lavish dinner prepared and served by a large staff of Moroccans. As the night progresses and the debauchery escalates, the Moroccans increasingly view the revelers as the godless “infidels” they are. When David and Jo show up late with the dead body of the young man in their car, word spreads among the locals that David has committed an unforgivable act.