In Kleo season 2 episode 2, titled Object Moni, we learn more about Nikolai while Kleo makes a trip to a sauna. Here's everything that happened in episode 2...
Nikolai is in his van looking at photos, he leaves it and is immediately attacked by masked men. Nikolai makes short work of the inept KGB men.
Kleo is looking through photo albums and files. She finds a picture of her granddad with Nikolai, the man who gave her the seahorse back. Rossbach is the third man in the photo, who was her instructor on Project Else. Thilo theorizes that the red suitcase is the part of her childhood that she's forgotten.
Kleo bumps into Jutta, a friend from the past. Kleo gives her short shrift and then interrupts Rossbach having some jelly. He asks what she wants, and she replies she has two questions. He identifies the man in the photo as Comrade Nikolai Zhukov. She then asks: So who was our man with the Americans in Clayallee? He replies: "I've no idea". Rossbach phones a mystery person and offers to take care of Kleo, but the mystery man says they will take care of Kleo. Kleo sees Rossbach and says she knows he's phoned Nikolai. He then tries to strangle Kleo with the phone cord.
Sven pays another visit to Reisser to try to find out about secret files which he hopes will help him identify who has the suitcase. Freddy spots that Reisser has a very expensive watch and after a spot of pressure, he admits to selling files to the KGB.
Kleo is lying by a phone but not dead. She heads off and finds Sven waiting outside KGB headquarters in Berlin. As Kleo gets out of the car, she slips a bug into Sven’s pocket. Kleo then tells the Soviet troops about Sven!
Sven is taken into the KGB headquarters and handcuffed. Jutta heads off to see Uwe. She says her friendly approach to Kleo was unsuccessful and Uwe isn't happy.
Sven meets his interrogator — Comrade Alexander Belov notes Kleo as she listens in. Yes, it's the man from Mallorca, who Kleo tied up naked in the previous series. Sven says he's after the files and offers a deal, Belov agrees to give him the files for a bribe and says to meet him at a sauna the next day for the switch. They switch it to a fairground tunnel after Sven complains he can't go to the sauna due to his blood pressure!
Outside her house, Kleo is stunned to find her old boyfriend Holger, who her grandpa banned her from seeing. But Kleo doesn’t want to see him and suggests it's not a good idea for them to see each other again.
Kleo goes to the opening night of Thilo's club. Kleo gives her approval to Thilo. Someone dressed like Santa on the dancefloor reminds her of her childhood and she has a flashback. And the Santa man says he's her dad… and Kleo wakes up in her bed.
Kleo heads off to the sauna and heats up the place so most of the men leave. She finds Belov and at gunpoint tells him to hand over the files. Sven heads to his meeting point with Belov and instead finds CIA Rose there. Rose offers Sven a load of money to get the suitcase and Kleo.
Sven is tempted especially by the idea of getting his own CIA badge! Belov takes Kleo, dressed in Soviet uniform, into KGB headquarters and Belov seems to give a coded warning to the woman on the desk. Belov opens the safe and gives Kleo the files. Guards then enter the safe room but Kleo knocks out the light and in the confusion flees. She gets as far as the front of the building but a machine-carrying guard blocks her path. But then a stun grenade lands at his feet and through the smoke comes Sven in a blue car!
The pair escape. And are soon arguing again. In the files, they work out that someone was operating under the codename The Bear and are now at a safe house. Kleo knows where the safe house is and with no further use for Sven kicks him out again much to his fury.
Kleo tells Thelo she's heading to Belgrade. Holger turns up again just as Kleo's taxi to the train station arrives. He hands Kleo a cassette of their old songs. Sven is watching from his car. At KGB headquarters Nikolai pays a visit to Olga who ordered his killing. Rather inventively he kills her with a Soviet flag!
He makes a call telling his comrades it's time to make their move. We then see a string of killings and hear a news report saying: "Moscow is currently reeling from a series of murders. Local authorities are now reporting 12 dead. The victims are reckoned to have KGB links…" All the victims were supporters of German reunification.