I Married a Witch
is a 1942 romantic comedy directed by René Clair and starring Fredric March and Veronica Lake. Lake is Jennifer, a witch who was burned at the stake along with her father Daniel sometime around the 1670s, after being accused by one Jonathan Wooley (March). Their ashes are buried under an old oak tree to prevent their spirits from escaping. Jonathan reveals that before she was arrested, Jennifer cursed him and all of his descendants to "marry the wrong woman".
A montage over the centuries reveals several generations of Wooleys (all March) who marry shrewish, henpecking wives. Cut to 1942, when a lightning bolt strikes the tree and frees the spirits of Daniel and Jennifer. They run across the latest Wooley, Wallace (also March) who is running for governor and also about to get married to another shrew, Estelle (Susan Hayward). Jennifer decides to make another Wooley miserable by making Wally fall in love with her. When Wally decides to go ahead with the wedding anyway, Jennifer makes a love potion to entrap him—but there's a mixup, and she drinks the potion instead. And as to be expected, Hilarity Ensues