"Alfred Hitchcock Presents" Murder Me Twice (1958)

At a house party, Lucy Prior allows herself to be hypnotized by Miles Farnham. While under his spell, she claims to be a woman living in 1859 and in the process of describing what she did, picks up a pair of scissors and kills her husband. In looking into the case, the coroner determines that in 1859 a woman did just as Lucy described but is suspicious that this could be a sham. At the inquest, Miles suggests that he hypnotize Lucy, with unexpected consequences.