It is hard to make a 25 page short story into a 2 hour movie, but it was done here with great effect by Sarah Phelps. The basis of the short story is kept while character development was expanded and subplots added. Great acting - the characters are believable. If you haven't read the short story by Agatha Christie or seen the movie with Marlene Dietrich and Charles Laughton, you will be shocked by the ending. Great entertainment. I highly recommend it.