The Farnsley Assignment

Janet Markham Bennett is just starting to feel as if she's getting used to her part-time job with her husband Edward's top-secret government agency. Their next assignment is something a bit different, though. This time the agency is sending them to the Bahamas to spend a weekend on a private island. Instead of being given a specific job to do, they're simply asked to keep their eyes open while they're there.
In spite of the rather vague assignment, neither Janet nor Edward is expecting their host, Arthur Farnsley, to get murdered within hours of their arrival on the island. To Janet it seems as if there are far too many suspects but no clear motive.
Can Janet and Edward work out who killed Arthur? Does his death have anything to do with the reason they've been sent to Farntopia? And can Janet maintain her cover for the entire weekend, even though that means acting nasty and spoiled all the time?