Investigator Alexandra Best is hired to find a missing woman. Caroline Price is deaf, a potential heiress and a reclusive crossword compiler. Alex discovers that Caroline has been having an affair with someone described as M. Is Gary, a young biker, involved in her disappearance -- or Caroline's own father -- or Jeremy Laver, Caroline's cousin, who will inherit her fortune if she doesn't claim it by her birthday? DI Nick Frobisher tells her never to ignore the obvious, but using Caroline's own clues Alex identifies M, as the search reaches a traumatic climax in an unlikely location.