The NCA are stunned when their French colleagues manage to hack EncroChat. They can see criminals' messages but not their identities. And the anonymous criminals have murder in mind...
The authorities identify dangerous criminals, who - unaware they've been rumbled - continue to share their alarming plans, from targeting enemies' families to building an underground torture facility.
The gangs realise that they've been rumbled. There's a murder, and the authorities fear a terrifying escalation when they uncover a vengeful plot to kidnap a criminal's family.
The investigation reveals a first: drug exportation from the UK: a half-tonne of ecstasy bound for Australia. And the authorities race to arrest hundreds of criminals before they can destroy evidence.