This marks the beginning of Margaret Rutherford’s series of four films playing Agatha Christie's eccentric "Miss Marple," known for her detective skills. The story opens with her observing a woman being strangled on another train while she is traveling home, and after reporting this to the police, who dismiss her account, she begins an investigation to find the person responsible, assisted by the somewhat unreliable “Mr. Stringer” (Stringer Davis). Arthur Kennedy, Muriel Pavlow, a suitably grumpy James Robertson Justice, and Ronnie Raymond in a clever performance all serve as obstacles for Miss Marple in this straightforward, enjoyable murder mystery that has a surprising element. The question arises: who would be so bold as to poison her duck curry?

Source on TMDB