Werewolf.

There are three children growing at Tammaru farm - one boy, Margus; and two orphan girls, Mari and Tiina. Margus' parents want him to marry Mari instead of Tiina as she is more their kind. Hotblooded Tiina is completely different from them and her mother was once executed for being a witch. Thinking that Tiina has bewitched Margus, Mari starts to publicly accuse her stepsister of being a werewolf.