With the help of opera singer Lucy O'Byrne, the doctors reveal the hidden muscle that makes you breathe. Dr Xand heads to a DNA laboratory to solve the mystery of who stole his strawberry milk and there is a chance to play along at home with another mind-bending trick. Meanwhile, the ouch-mobile is open for business, and over in accident and emergency one patient has cut their eyebrow and another has stapled his own finger.
