Saara is put to work combing through the text in the virus, looking for passwords. It's a monotonous job, but after many hours she finds a suspicious line of encrypted text within the code. Her colleagues think it's unimportant, but Saara isn't convinced. She also gets more familiar with the players at GCHQ and makes some unlikely friends. With their help, Saara unravels a dubious invitation to rendezvous - but is she closer to the truth or just willingly entering a carefully baited trap?

With Danny unconvinced by Saara's exchange with a whistleblower, she's in a difficult position, but a revelation from Kathy forces Saara's hand. Meanwhile, Marina takes up a new opportunity in London.