On-board the MV Helios, cruising around the Mediterranean, copywriter David Ansell is seeking inspiration to write a glowing account of his voyage for the ship's owner, Rex Cruising Company. His inspiration comes in the form of the blonde and beautiful Melanie Caine and they are inseparable for the rest of the cruise.
Back home in suburbia with his wife, Ansell is pining for Melanie, so is delighted to get a call from her summoning him to meet her – along with the toy monkey she asked him to take through customs for her. When she doesn't turn up, he assumes she's got cold feet and no longer wants to pursue their relationship. However, when reports of a woman's body being found, horrifically tortured, are aired on the news – and Ansell's home is broken into with tragic consequences – it seems there's something that Ansell may have that someone will do anything to find . . .