What is hair and how do we go bald?

Ollie is a 28 year old hairdresser from Cheshire, he started losing his hair when he was still in his teens. He feels self conscious about his rapidly receding hairline and has decided to have a hair transplant. Working in the hairdressing industry he is constantly surrounded by the hairstyles he wishes he could create for himself, which has really affected his confidence. But what is hair and how do we go bald? Computer graphics go inside Ollie's scalp to see how hair grows and what is causing Ollie to lose his hair at such a young age.