The doctors use real stomach acid to do an experiment to reveal how the digestion process starts. Also, Dr Chris proves that the younger you are, the more sounds you can hear. Meanwhile, over in accident and emergency, one patient has broken his arm tripping on a kerb and another has banged his head on the handlebars of his bike.

Dr Chris and Dr Xand show you an awesome body trick to amaze your friends with, and reveal another way your brilliant body heals itself if you get injured. The doctors also look at some of their best bits of Operation Ouch! so far.