The acerbically witty and severely facially disfigured broadcaster Adam Pearson presents a personal film about genetics. He and his twin brother Neil are genetically identical and both share the same genetic disease, Neurofibromatosis 1 (Nf1) - yet they are completely different. Adam's face is covered with growths, whereas Neil has none. Neil has short-term memory loss, whereas Adam is razor sharp.

How can the same genetic disease affect identical twins so differently?

Adam is on the cusp of a successful film and television career, but the disease has left tumours on his face that are growing out of control and he could lose his sight. For years, everyone thought Adam's brother Neil had escaped symptoms, but today his life is governed by epilepsy and a mysterious memory loss that suddenly came on during his teens.

Determined to save their future, Adam tries to find out why the disease affects the twins so differently and see if there is anything he can do to stop it from tearing their lives apart.

Horizon Season 55 Episodes...

• s55e01 - The Immortalist
• s55e02 - Project Greenglow
• s55e03 - The Mystery of Dark Energy
• s55e04 - Oceans of the Solar System
• s55e05 - The End of The Solar System
• s55e06 - How to Find Love Online
• s55e07 - Ice Station Antarctica
• s55e08 - Curing Alzheimer's
• s55e09 - E-cigarettes: Miracle or Menace?
• s55e10 - Why Are We Getting So Fat?
• s55e11 - Doping
• s55e12 - Inside CERN
• s55e13 - My Amazing Twin
• s55e14 - Jimmy Carr And The Science Of Laughter
• s55e15 - The Lost Tribes of Humanity
• s55e16 - The Wildest Weather in the Universe

Horizon Show Summary

Horizon is BBC Two's flagship 50-minute science documentary series.

Recognised as the world leader in its field, it regularly wins a sweep of international science, medical and environmental film accolades, and has recently won the Royal Television Society Award and the Prix Italia.

In 2002, the British Academy of Film & Television Arts presented Horizon with the BAFTA Television Award for Best Factual Series or Strand.

In 2003 it won the prestigious Images et Science award for best medical documentary and the Carl von Linne Award at the Living Europe film festival in Sweden. That year, a Horizon co-production with WGBH Boston won the Emmy for best documentary.

In September 2014 it celebrated its 50th anniversary and it continues to enjoy outstanding critical acclaim.