Dr Xand goes underwater to show how your blood clots, and Dr Ronx finds out how echolocation - an amazing navigation technique used by bats to fly in the dark - is helping visually impaired patients. There's a new body trick to make things look bigger, and it's time to meet our first ever Ouch Award nominees. Meanwhile, in the emergency department a broken leg requires surgery after a clash with a diving board and another patient has their finger stuck in a toy truck.