Episode 1 - Marvellous Muscles

Identical twins Dr Chris and Dr Xand van Tulleken experiment and explore their way through the fascinating world of medicine and biology. Chris and Xand will let the viewer in to their exclusive world of medicine and explain the awesome things our bodies can do. The doctors experiment on their muscles to show how they work. Dr Chris meets some wriggly maggots that are helping to heal a sore foot, and Dr Xand goes on call with an emergency ambulance team. Meanwhile, over in accident and emergency, one patient has some grit in his head after a fall in the playground and another has injured his neck after performing a karate kick.

Episode 2 - Your Brilliant Brain

Identical twins Dr Chris and Dr Xand van Tulleken experiment and explore their way through the fascinating world of medicine and biology. The doctors show what really happens when you sneeze! Dr Chris gets his hands on a real human brain and Dr Xand goes on call with an emergency ambulance team. Meanwhile, over in accident and emergency, one patient has a hook caught in their hand and another thinks he's lost a toenail up his nose.

Episode 3 - Secret Lifesavers

The doctors demonstrate how our body movements are controlled by confusing their own brains. Dr Chris lets a blood-sucking leech feed on his arm and Dr Xand goes on call with an emergency ambulance team. Meanwhile, over in accident and emergency, a patient has locked their jaw wide open and another needs stitches after a particularly nasty fall.

Episode 4 - The Coolest Feet in Town

The doctors see how much pain they can take in their laboratory, Dr Xand investigates how our shoes can dramatically change the way we walk and Dr Chris goes on call with an emergency ambulance team. Meanwhile, over in accident and emergency, a patient comes in with a suspected hand fracture and another may lose his fingernail after trapping his finger in a car door.

Episode 5 - Your Connected Body

Dr Chris inserts a special medical tube into Dr Xand's nose and down to his belly to prove that the nose, mouth and stomach are all connected. Dr Xand takes things to the extreme as he endures a room colder than Antarctica to find out how our bodies cope in freezing temperatures. And Dr Chris is in the operating theatre to see an incredible robot surgeon perform a real-life surgery. Meanwhile, over in accident and emergency, one patient has a broken elbow after a game of leapfrog goes horribly wrong, and another has managed to get a stone stuck in his ear.

Episode 6 - Don't Be Sick in the Sky!

Dr Chris takes a terrifying, stomach-turning ride in an aerobatic display plane to explain what happens to your body when you feel travel sick. The doctors put on their pyjamas to investigate all about sleep, and Xand finally finds out if he really does snore! Also, Dr Chris goes on call with an emergency ambulance team. Meanwhile, over in accident and emergency, one patient is suffering from mysterious tummy pains and another has an injured hand after an accident involving a race in a high-heeled shoe!

Episode 7 - Episode 7

Dr Chris demonstrates how vocal chords work and explores how the human body deals with fear. Dr Xand goes on call with an emergency ambulance team. In Accident and Emergency, one patient is admitted with serious stomach aches and another has a sore elbow.

Episode 8 - Episode 8

The Doctors experiment with urine. Dr Chris explores the damage snake venom can do to the human body. In Accident and Emergency, one patient has a hole in his head after crashing his bike and another has a black eye.

Episode 9 - Bruised or Broken?

he doctors investigate what happens when blood is full of oxygen by whisking up a blood smoothie! Dr Xand visits a special medical collection of body parts to find out some ways in which human organs can go seriously wrong, and Dr Chris goes on call with an emergency ambulance team. Meanwhile, over in accident and emergency, a new admission has a seriously battered face after a bike accident, and another has a nasty infected finger from picking at his fingernails.

Episode 10 - Your Bones Are Alive

Dr Chris swallows a supercool camera pill to follow the journey that food makes through his body. Dr Xand explains how strong our bones are and meets someone who has developed the technology to grow bones in a laboratory. Also, Dr Chris is put to the test as he takes part in a realistic mock surgery scenario. Meanwhile, over in accident and emergency, one patient's race to the finishing line means a trip to surgery to fix a broken elbow, and another is admitted with a sore eye and blurred vision.

Episode 11 - What a Stink?!

Doctors take on their smelliest investigation yet when they find out how the shape, size and pong of your poo can tell you a lot about your health! Dr Xand visits the largest blood factory in the world and donates his blood to see how it is processed to help save lives. And Dr Chris spends time with the Midlands air ambulance crew; an awesome airborne emergency service which can get to the scene of an accident quickly. Meanwhile, over in accident and emergency, one patient has been admitted with a deep cut to her hand after slipping on some glass and another has to have a gash on his head glued together after crashing into a tree stump.

Episode 12 - The World’s Stretchiest Skin

Episode 13 - What is an Allergy?

The doctors investigate how skin protects the body from extreme temperatures by dipping their hands in a liquid so dangerous it can freeze on contact. Dr Chris visits an allergy clinic to find out all about allergic reactions and meets two patients who have their suspected allergies put to the test. And the emergency ambulance team comes to the aid of a lady with severe tummy pains. Meanwhile, over in accident and emergency, things get fruity as one patient is admitted with a broken 'banana' arm and another needs treatment for a burn after dropping fried onions on her foot.