There's no single narrative serving 9/11. For millions, the fateful day is both tragedy and triumph--a sorrowful low point mixed with the best of endurance and hope. But it's not just a human experience. More than 300 rescue animals--the most in U.S. history--were deployed after the towers fell. Some comforted, some searched, and one even guided her blind owner to safety from the 78th floor of the North Tower. What follows are a few stories of unique and remarkable feats from these unlikely heroes.