Dead Man's Island.

Henrietta O'Dwyer Collins, called Henrie O., is a world-famous journalist and writer. She's invited by her old lover Chase Prescott to his secluded island home. Chase, a wealthy businessman with money woes, hopes Henrie O. can discover the person he thinks is trying to kill him. It seems like she has her work cut out for her. Possible suspects include Chase's much younger wife, his son, and many others.