Roscille visits Fléance in the dungeon. She tells him they could have been allies but that now she cherishes vengeance and anticipates his death. He says his father was a good man. He wishes he’d raped Roscille. He tells her he knows she slept with Lisander and threatens to tell Macbeth, saying she’ll suffer a “whore’s” death. She struggles to keep her composure at the sight of the dungeon and at his words.

Macbeth finds her outside the dungeon. He asks if the story of the men attacking her was real, and she says she suspects it was Fléance’s cronies. She claims she started doubting Fléance and Banquho while he was gone because they refused to torture Lisander but that she didn’t tell Macbeth out of fear of retribution. Privately, she hopes this will undermine Fléance’s story about her adultery. Macbeth tells her they must have no secrets and that Fléance will be killed. In order to counter the prophecy, he says they must have sex every night until she becomes pregnant. If the child is a girl, she will be killed; Roscille worries for her own life too in this scenario.