Bill Spedding, a washing machine repair man, was accused of abducting three-year-old William Tyrrell. The little boy, dressed in a Spiderman suit, vanished without a trace in 2014 from the front yard of a family home. After initially treating his disappearance as a missing person case, the police zeroed in on Bill Spedding as their key ‘Person of Interest’, believing he had taken the child. Four Corners investigates how the police built their case against Bill Spedding.