Journalist Charlie Webster has covered some of the biggest sporting events in the world. But there was one story she was never able to tell. Until now.

On Monday, Four Corners tells the story of what happened to a group of young female athletes who were groomed and abused by their running coach.

In a personal investigation Charlie Webster sets out to find her teenage running friends who all dreamt of becoming Olympic athletes, to learn the truth of what happened to them at the hands of a manipulative predator.