The Lighthouse by P.D. James

Combe Island off the Cornish coast offers respite to over-stressed high authorities who require privacy and security. But demanding author Nathan Oliver is found strangled and hanging from the renovated lighthouse. Investigator Adam Dagliesh, his inspector Kate Miskin, and sergeant Francis Benton are all pre-occupied with their personal and love lives. The first victim was thoroughly disliked by visitors and residents for valid reasons, but the second, a recovered alcoholic priest, was admired by the skeleton staff. Suspects include Oliver's daughter Miranda, editor Dennis, animal researcher Dr Yelland, recently orphaned Dan, aged Emily, boatman Jago, sickly Dr Speidel, physician Dr Stavely and his unfaithful wife Jo, administrator Maycroft, housekeeper Mrs Plunkett, cook Mrs Burbridge, rebellious teen Millie. Past murders are uncovered and SARS threatens the island.