Portrait of Alison is a 1956 British atmospheric crime film directed by Guy Green. It was based on a BBC television series Portrait of Alison which aired the same year. In the United States the film was released as Postmark for Danger. It was also known as Alison.

Plot
The film opens with a car plunging over a cliff in Italy. The killed driver is newspaperman Lewis Forrester. The woman with him is supposedly Alison Ford, an actress. But she wasn’t actually in the car and turns up later in England to try and solve what was in truth a murder to shut the newspaper man up, not an accident. She solicits the help of Forrester’s brother, Tim, an artist. Then, as the story unfolds, a number of mysterious, unsolved questions keep emerging, along with two more murders and a suicide. And before it’s over it has been learned that an international ring of diamond thieves is at the bottom of everything, that no less than four of the major characters are part of it, and that an independent blackmailer is at work as well.

Cast
Terry Moore as Alison Ford
Robert Beatty as Tim Forrester
William Sylvester as Dave Forrester
Geoffrey Keen as Inspector Colby
Josephine Griffin as Jill Stewart
Allan Cuthbertson as Henry Carmichael
Henry Oscar as John Smith
William Lucas as Reg Dorking
Terence Alexander as Fenby
Sam Kydd as Bill, the telephone engineer