context: The Virgin Spring tells the story, set in the late medieval Sweden, of a prosperous Christian whose daughter, Karin (Birgitta Pettersson), is appointed to take candles to the church. Karin is accompanied by her pregnant servant Ingeri (Gunnel Lindblom), who secretly worships the Norse deity Odin. Along their way through the forest on horseback, Ingeri becomes frightened when they come to a stream-side mill and the two part and Karin sets out on her own.
  Ingeri encounters a one-eyed man at the stream-side mill. When Ingeri asks about his name he enigmatically responds he has none "in these days". The man tells Ingeri that he can see and hear things others can not. When the man makes sexual advances towards her and promises her power, Ingeri flees in terror. Meanwhile, Karin meets three herdsmen (two men and a boy) and invites them to eat her lunch with her. Eventually, the two older men rape and murder Karin while Ingeri watches, hidden, from a distance. The two older men then leave the scene with Karin's clothing. The younger (a boy) is left with the body and to watch the goats, but he takes the situation poorly and quickly becomes sick with guilt.
  The herders then, unknowingly, seek shelter at the home of the murdered girl. Her parents, played by Max von Sydow and Birgitta Valberg, discover that the goat herders murdered their daughter when the goat herders offer to sell Karin's clothes to her mother. After they fall asleep, the mother locks the trio in the chamber. Ingeri returns to the farm and breaks down in front of the father; she tells him about the rape and confesses that she secretly wished for Karin's death out of jealousy. She does not mention her encounter with the one-eyed man. In a rage, the father stabs one of the herders to death with a strange dagger before killing the other two with his bare hands.
  That same day, the parents set out to find their daughter's body with the help of Ingeri. Her father vows that, although he cannot understand why God would allow such a thing to happen, he will build a church at the site of his daughter's death. As her parents lift her head from the ground, a spring begins to flow from where she was lying. Ingeri then begins to wash herself with the water and Karin's parents clean their daughter's muddied face.
question: Who rapes and murder Karin?
answer: three herdsmen