Agatha Christie made this for the stage and it shows. Dietrich is weird, unattractive and hackneyed here, a frosty scheming German who spends the dying parts of the movie pretending to be a woman overpowered by her emotions. The occasional good line for the barrister does not make up for the myriad dei ex Christies. I'm sure her fans think it really does rank around #150 in the IMDB top-250, but there's no need to inflict this stuff on the rest of us.