And Then There Were None - Agatha Christie. One of my favorites when I was younger! This particular book left the longest lasting impression on me...more so than the others, although they left impressions with me as well. This one, I remember the best.
Eight strangers are invited by a mysterious person named U. N. Owen to a luxurious mansion on an island off the coast of Devon. Waiting for them on the island are the housekeeping couple, Mr. and Mrs. Rogers. After dinner, the group hears a recording in which a disembodied voice exposes each of them as a murderer whose crime has has gone undetected and unpunished.