Section D are forced to welcome an FSB Officer onto the Grid to help track down Aibek, a rogue nationalist from the ex-Soviet state of Azakstan.
Aibek is in the UK to find the last known sample of the nerve agent 'Paroxocybin'. The chase is on, but will the team find a way to stop the nerve agent falling into the wrong hands without ruining Anglo-Russian relations?
Meanwhile, Lucas's personal life takes a passionate turn.
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