Spotlights on people whose bodies amazed doctors and defied expectations.
It's a race against time for a child with an extraordinary neck growth, and there's a medical revelation for a 31-year-old woman trapped inside the body of a baby.
Meet conjoined twins joined at the head, who beat the odds to survive, and a toddler addicted to smoking who faces dramatic consequences.
Ignacia suffers from a facial tumour that could asphyxiate her. Thomas has a rare bone eating disease that has ruined the left side of his torso.
Meet the miniature five year old who is defying all the odds, and can doctors treat the mystery of Indonesia's incredible tree-man?
Three-year-old Ana suffers from a brain crushing prematurely fused skull. Alex had septicaemia that rapidly led to the amputation of all four of his limbs.
Rebecca vomits up to 12 times an hour and is often hospitalised. Jacque has a lymphatic malformation in her face that means she has never talked.
Darina was born with a genetic disorder that's left her with a deformed mouth and jaw. Isaiah was born with his organs back to front and no jaw at all.
Fatima is allergic to light and even indoors must take precautions to avoid succumbing to skin cancer. Amar's face has been destroyed by a bony tumour.
Mahesh weighs 150kg, twice the weight of an average man, due to a syndrome that encourages constant eating. A development in the womb left Christian with no eyes.
Sulaiman suffers from Cruzon syndrome, which causes his eye to fall from his skull. Tony became a hermit when huge lumps grew around his face.
In Peru, diver Alejandro's body has blown up like a balloon. Marc from Germany has to drink 20 litres of water every day or risks death. Will doctors offer a cure?
Italian professor Letitzia feels no physical pain and has broken limbs with no discomfort. Filipino twins Czarina and Ciara, 7, were born joined at the head.
In India, Arpit was born with his heart positioned on the outside of his rib cage. In Brazil, Winny suffers from a rare disorder that means her skin falls off.
In Mexico, Adrian, 22, has a basketball-sized tumour on the side of his face. In the US Janice has a giant leg that has grown out of proportion to the rest of her body.
In Mexico Dany, 8, was born with Moebius Syndrome which paralysed her face. She's set to undergo delicate microsurgery. Will she smile for the first time?
Lee, 42, from England, has a rare stomach disorder that means his body is eating itself. In Columbia, Edward is just 70cm tall. Can a specialist explain it?
In India, baby Chahat weighs as much a six-year-old. Her family travel 2000kms to see a top obesity expert. In Spain, Juana is allergic to the outside world.
When Richard, 43, was shot in the face he underwent a face transplant, but now has complications. In a Peruvian village boys and men are going blind.
American toddler Cora was born with a condition causing her hands to swell up. In Brazil, Judite, was born with deformed legs and spine and walks on all fours.
A German woman blind in one eye has pioneering surgery where one of her teeth is used to hold a lens in her eye. Teenage Indian brothers are joined at the hip.
The UK's shortest married couple both have dwarfism and are expecting their second child. In India, Miria is three and has a severe cleft palate.
A baby with a rare syndrome battles to survive and meet a young boy who adores playing football, even though he was born without feet.
Meet Thailand's werewolf girl, the eight-year-old girl who weighs the same as a heavyweight boxer and can doctors solve the mystery of the girl who cries blood?
Meet the mysterious 'bubble man' of Jakarta, the teenage beauty who grew into a giant and the world's tiniest teen, but will she achieve her big dreams?
In Brazil, a man has an upside-down head; triplets undergo a second round of life-saving surgeries and an Argentinian has giant-sized limbs.
A Puerto Rican boy's face is melting, doctors tend to an Afghan baby with a parasitic tumour and a Brazilian girl's feet keep growing.
A girl has a terminal neck tumour, and one woman has a black and white body and the other has the world's largest hands.
A British man is literally scared stiff. A Thai man would be the tallest man on earth if he could stand, and a toddler is covered in hair.
Travel around the globe and meet extraordinary individuals who suffer from conditions so rare and mysterious that the medical world is often baffled.
Meet Vinicio Rivo, the man who suffers from neurofibromatosis, and who was kissed by Pope Francis. Plus, meet the world's hairiest family.
In Nepal, a man just 16 inches tall campaigns for the record of smallest man. Plus, a black and white Brazilian family is bullied and the elephant man gets married.
The stories of people round the world who suffer from rare medical conditions, including a man with a life-threatening tumour twice the size of his head.
Uncovering stories of people round the world who suffer from rare and mysterious medical conditions. Some require surgery so complex that the odds of survival are minimal at best.
Guarab, two, was born with an extra arm growing from his back. His family weigh up the pros and cons of having an operation to remove it.
Godfrey, 47, won the title of Uganda's most unusual looking man. Follow him as he searches for a diagnosis for his dramatically misshapen head.
Arun, from India, has four legs, with the second pair growing from his back. He goes to Delhi for an operation. Can doctors help - and will his family agree?
Laisha, eight, from Texas, is just 70 cm tall with a rare form of dwarfism. She visits the region of Ecuador where hundreds of people have the same condition.
Laxmi, from India, was born with a huge facial tumour giving her the appearance of the Hindu god Ganesh. Can surgeons save her face?
In Sweden, Kim's had dozens of surgeries on a huge facial tumour, but stopped after he almost died. He needs one more operation - can he go through with it?
Khalida goes to a hospital in Kashmir after suffering intense stomach pains. Doctors operate and are astonished to discover the world's biggest ovarian cyst.
An Indian girl suffers from an infestation of ants in her ear canal. And, a Brazilian woman's tiny facial birthmark has become a huge tumour despite 19 surgeries.
A Romanian boy's face grows too fast, slowly choking him to death, and doctors try a possible treatment. Plus, a child was born with an extra arm on his back.
An English girl whose limbs had to be amputated when she was born is fitted for prosthetics. A Polish man is the world's first recipient of a donor hand.
A Brazilian woman's condition causes thousands of tiny tumours that bubble her skin. Plus, a 4-year-old boy in India has an enormous foot.
A young Brazilian boy was born without eyes, and the family hopes to have prosthetic eyes made. Two brothers in Nebraska suffer a rare bone loss condition.
An Indian woman gives birth to a baby boy with the head and arms of his dead twin brother attached his chest. A Brazilian woman seeks treatment for her giant leg.
Uncovering stories of people around the world who suffer from rare and mysterious medical conditions. Some need surgery so complex that the odds of survival are slim.
A 16-month-old toddler undergoes surgery to remove a life-threatening facial tumour. Plus, a girl has an operation on her skull to allow her brain to grow.
Two feet tall brothers were hidden from the world for years because they were considered cursed. Plus, a boy's brain tumour causes violent seizures.