The high-flying action-packed world of undercover Customs and Excise investigators and their fight against international crime comes together in the 1990s ITV drama The Knock

The Investigations Unit of HM Customs and Excise comprises a crack team of young detectives. They are civil servants with a difference - when they 'knock' - people jump! From their top security head-quarters they lead cases which are frequently undercover, often life-threatening and involve everything from arms trading to illegal gold and drug smuggling.

This set contains all seven episodes of the first series, available for the first time on DVD