We are all surely familiar with those stories of naive young Brits who travel abroad and are persuaded by a charming new holiday friend to bring back what they’re told is an innocuous package, only to end up on the sharp end of drugs smuggling charges. The latest series of the BBC’s World of Secrets somewhat inverts those expectations: it tracks the fortunes of three innocent young Brazilian sailors and a French captain who were allegedly duped by a Norwich businessman into sailing a rackety yacht across the Atlantic with £100 million worth of cocaine hidden in the body of...