In Shakespeare's "Macbeth," the phrase "What's done is done" encapsulates the themes of guilt and acceptance. It reflects the protagonist's recognition that actions have irreversible consequences. After Macbeth and Lady Macbeth commit regicide, they struggle with their guilt, but this statement highlights their attempt to move past their deeds, acknowledging that they cannot change the past.

This quote illustrates the tension between ambition and morality, illustrating how the rush to power leads to tragic outcomes. Ultimately, it serves as a reminder of the heavy price of their actions, showcasing the psychological torment that follows their pursuit of power.