An armed robbery at a fashion show where thousands of pounds worth of clothes are stolen perplexes the squad. Matters are complicated by obsessive Dutch detective, Pieter Kluivert, who is looking for assistance in capturing the arms dealer who murdered his son. Kluivert is convinced that the robbery is linked to his case.
When plastic explosives are stolen from an army truck newly installed DCI Nick Hall is convinced that the hijacking was committed by a gang, "The Sewer Rats", that he pursued back in the seventies. Matteo and the rest of the team are sceptical but slowly start to come round to their new chief's way of thinking as the case develops.
The pregnant wife of an armed robber turns to crime herself, holding up a baby shop and accidentally shooting a security guard. The Flying Squad are put on the case and when, encouraged by her sister, she commits a second robbery a jewellery store she goes into labour with the squad closing in.
A gang of villains, in need of a big score, return to Britain from Spain and quickly hijack a lorry of computer parts. However, on their escape two traffic officers come near to foiling their plan and are gunned down by the gang. The dead officers' boss, Chief Inspector Sansom, is an old friend of Hall and presses Hall to put his team on the case.
Matteo and the squad investigate a robbery on a gold bullion warehouse. The links between one suspect, a veteran armed robber, and a local stripper provide the most obvious line of investigation. Meanwhile, Hall uses his connections in the Asian business community to look into the local gold trade leading him into danger.
The Flying Squad foil the attempted kidnap of a Japanese metal trader by the Mafia. Their investigation sees the squad caught in the middle between the Mafia and the Yakuza as war threatens to break out. Meanwhile, D.C. Oxford has been taken off active duty and is bottling up his feelings over the shooting of Garry Parker.
An unarmed Oxford is caught in the middle as the Mafia and Yakuza do battle in a shootout trying to capture the witnesses being guarded by him and McCarthy. As the two sides come closer to war, the team try everything to find Takahashi whilst trying to avoid being caught in the crossfire.