“Intheearly1990s,attheheightoftheinternationalwarondrugs,thegovernmentagencyinchargeofBritain’sborders,HerMajesty’sCustomsandExcise,realizedthattheywerelosingthebattleagainstdrugsmuggling.Theirsolutionwasextraordinary,”readsthelogline.“Inatop-secretoperation,asmallteamofBritishCustomsemployeesweresentundercover.Theirtask...