The season finale centers on the fallout of the Russian plot to stage a "revenge" mission against MI5.
The primary threat involving a potential "bomb" at the Glasshouse skyscraper is revealed to be a diversion. The true goal of the Russian mastermind, Nikolai Katinsky, was a cyber-attack aimed at depleting MI5's "slush funds" as an act of financial sabotage. "Slow Horses" Last Stop(2022)
Jackson Lamb tracks Katinsky to a remote location. In their final confrontation, Katinsky reveals his personal vendetta: he blames Lamb for the death of his former colleague. Rather than being captured, Katinsky chooses to take his own life after Lamb exposes the futility of his mission. The season finale centers on the fallout of