While Lady Macbeth appears to be looking back at the previous murder, Macbeth looks forward, anticipating the next murder, of which Lady Macbeth is not yet fully aware. That distinction between their two states of knowledge allows Shakespeare to play once more on the power relationship between husband and wife. Here, then is yet another reversal of character, and it is shown in two major ways: first, by Lady Macbeth's innocent-sounding questions and, second, by Macbeth's adoption of animal imagery. In Act I, Scene 5, Lady Macbeth was the one who spoke of "the raven" and "the serpent." Now Macbeth takes on the same language of horror, imagining his mind to be "full of scorpions," and speaking of the "bat" and the "shard-born (dung-bred) beetle."