I have long been a fan of agatha christie; but no matter how good the sourece material is, the director and actors and screenwriters somehow have to pull it off when they decide to make a movie. Well, in this fantastic flim, Billy Wilder et al certainly do. What a cast. Detrick, Power, Laughton and all the rest, because there isn't a missed note anywhere. I would say most of the movies (or books) I have read that have a twist ending have rather soured on reflection... but not this one. Even if you know everything, it's still enjoyable to watch. What a treat when everything clicks. Of course I realize it is a kind of magic, like capturing lightning in a bottle. Don't miss this one.