Crimewatch File reconstructs the inside story of a major police investigation. A uniformed police officer is shot dead during a routine enquiry in the centre of Leeds and police face an apparently motiveless crime. The killer leaves few clues. Not since the 'Ripper' murders have West Yorkshire police been confronted with such a massive enquiry. The investigation involved four police forces, and reached its unexpected and dramatic climax two-and-a-half years later.