Other People's Letters (1975)

Original title: Чужие письма

Zina is sixteen. She is a manipulative schoolgirl living in a small Russian town among sincere and simple people. Zina is nice on the surface, but so unable to enjoy normal life, that she is desperately trying to hurt someone. She tries to seduce and compromise a handsome young man, but he is smart enough to see through her and escapes from her trap. Zina manipulates her classmates so she looks like a victim. Now Zina's teacher, Vera, a sweet and loving lady, takes care of her trying to save the troubled girl, but in return, Zina becomes extremely crafty to hurt the teacher.