"Charles Wallace had once again been contemplating the intricate model of the tesseract. He spoke softly to his sister. "Meg, no matter what happens, even if Dennys is right about her heart, remember that it was herself she placed, for the baby's sake, and yours, and Calvin's, and all of us--" Meg looked at him questioningly. Charles Wallace's eyes as he returned her gaze were the blue of light as it glances off a unicorn's horn, pure and clear and infinitely deep. "In this fateful hour, it was herself she placed between us and the powers of darkness."