Dr Chris and Dr Xand van Tulleken are back to track down the most awesome, epic and incredible things in the universe! This time it's all about big animal emergencies. In this episode they find out all about dolphins and sharks and what makes them such amazing swimmers. Clare Balding goes to Okinawa in Japan to find out if a fake tail for Fuji the dolphin will help her to swim and jump again, and Professor Brian Cox swims with some great white sharks to find out why they're the fastest predators on the planet. Show less