The conviction of Gary Allen is the culmination of more than 20 years of investigations which included a two-year undercover operation involving a total of seven officers.Humberside Police were so concerned about the danger Allen posed to women that they built a world around him populated by police officers posing as his friends plus their girlfriends and family.And this huge investment in Operation Misty paid dividends when Allen confessed to the murder of Samantha Class to an officer named in court only as Ian.The recording of Allen’s confession to Ian was crucial when the Director of Public Prosecutions successfully applied to the Court of Appeal to quash the not guilty verdict reached by a jury in 2000.