A good story, and that could be a good movie.

Guy Brouard, septuagenarian and millionaire, was killed on the island of Guernsey. Quickly the police arrest a young woman China Rivers, American. Cherokee, brother of China, seeks help to Deborah St James, China childhood friend, and her husband Simon, who works in London in forensics. They land on Guernsey to conduct a parallel investigation. Indeed it appears that the local police quickly is very pleased to have found an alien guilty, which suits everyone on this small island where everyone knows everyone.
The personality of Guy Brouard will prove to be much more complicated than it seems at first. A dozen people revolves around the victim, everyone almost had a reason to kill Guy. He had a complicated psychology, he loved manipulate people to do admire, make them his forced, etc ... If we add to this the usual reasons (money, love, jealousy, etc ...) the possible culprits and motives are numerous unofficial our investigators. Especially as the possible culprits almost all have something to hide. Therein lies the problem: such a collection of individuals, with such ambiguous reports, complicated, intricate, is only possible in a novel! One could say that the author has done too much, but on the other hand, this gives us a great plot, a survey advancing to blow never obvious revelations and twists. The end will surprise many.
Disappointment: I liked that the investigation is also an excuse to go and discover Guernsey, but that is not the case. All trips by car, necessary for the investigation, lead to the same conclusion: Guernsey is small, the road network is deplorable, signage is nonexistent! There is surely more to say on this island.