A sinister conman looking for a mysterious doll visits the apartment of Sam Henderson and his blind wife, Susy. With Sam potentially implicated in a recent murder, Susy realises the doll could be the key to his innocence and refuses to reveal its location. A deadly game of cat and mouse then ensues between the two of them and Susy knows the only way to play fair is by her rules, so when darkness falls she turns off all the lights leaving both of them to manoeuvre in the dark until the deadly game is over.
From the author of Dial M for Murder. Frederick Knott's thriller is the story of Susy Henderson, a recently blinded housewife who unwittingly possesses a doll filled with illicit drugs. Harry Roat, a brutal and sophisticated criminal, coerces two small-time thugs into helping him con Susy into giving up the doll. A battle of wits ensues as Susy and the young girl upstairs launch a counterplot against the thieves.
The drama plays on the themes of darkness and light as Susy navigates through her sightless world, and the crooks signal each other with light through the Venetian blinds.