Justine is accused for the murder of William after finding a picture of William's mother in her pocket. Justine falsely accuses herself and is sent to jail.
Feeling pressured about the accusation, Justine succumbed, confessed a lie, and is ready to die.
As Victor and Elizabeth visit Justine and explains to them she can't live her life anymore and that she's ready to die. Victor feels guilty for the secret role he plays in William/Justine deaths. Elizabeth can't see the world the same way after witnessing the execution of an innocent.