- "This gives me no pleasure, it really doesn't... But I have been given a job to do. So please, answer the questions that I was told to ask, or I will begin breaking you, a piece at a time."
- ―Sergei to Claire Temple
Sergei was a mobster that worked for Vladimir and Anatoly Ranskahov, undertaking their most violent and cruel jobs. He remained loyal to the Ranskahovs during their war against Wilson Fisk, losing his life in the process.
Torturing Claire Temple
Under the order of the Ranskahov brothers, Sergei and Dmitry searched the apartment of Claire Temple, who they were aware was connected to the Man in the Mask. They failed to find Temple in her apartment but they were able to get her location after they found and tortured her neighbour Santino. They found Temple in her friend's apartment where she had been staying; they dragged her from the apartment as she tried to call for help and threw her into the back of a taxi.
Once they were back at Veles Taxi, Sergei began torturing Temple and demanding to know the location and identity of the Masked Man, but Temple continued to deny any knowledge of the man's name or where he was. Sergei began to lose his temper and smashed the window of a taxi before coming close to killing Temple by hitting her in the head with his baseball bat. Dmitry reminded him of Vladimir Ranskahov's orders for her to be kept alive until they had the information they needed from her; knowing how dangerous and ruthless the Ranskahovs could be, Sergei relented.
Before Sergei could continue torturing Temple, the lights throughout the warehouse were suddenly shut off without warning. Temple began to laugh hysterically as she knew this meant the Masked Man had finally come to her aid. Unable to see in the darkness, Sergei's men were attacked and knocked out by their attacker. Seeking to defend himself, Sergei grabbed Temple and held her at gunpoint. The masked man was able to attack Sergei and broke his hand before Temple knocked him out with his own bat.
Shortly after the incident, Vladimir and Anatoly Ranskahov returned to the Veles Taxi Garage and discovered the wreckage left behind by the skirmish. Vladimir went over to Sergei, who was still too weak to stand due to his broken hand and a head injury, and demanded to know what had happened, so Sergei confessed that it was the Masked Man who had attacked them. Knowing their organisation was in danger, Anatoly chose to accept Wilson Fisk's offer for a buyout, despite Vladimir's reservations.
War with Wilson Fisk
- "The men are ready at the other locations?"
"They're waiting for the call."
- ―Vladimir Ranskahov and Sergei
Sergei was present when James Wesley came to Vladimir Ranskahov's office to discuss their deal; however he appeared to be concerned with Anatoly Ranskahov's absence. The question was soon answered when Anatoly's corpse was brought into Vladimir's office, with his head having been removed. Sergei watched alongside Wesley as Vladimir searched his brother's body and discovered a black mask in his jacket pocket, leading him to believe that the Masked Man was responsible for his brother's brutal murder.
While Vladimir Ranskahov was cleaning his brother's body, Sergei informed him that Turk Barrett claimed to have information about Anatoly's death. Barrett informed him that he had learned that Wilson Fisk and the Masked Man were working together. With this information Ranskahov became convinced that Fisk had betrayed them and was responsible for his brother's murder; in response he ordered Sergei to get all his soldiers ready with all their weapons and prepare for war. When Sergei questioned if he really meant all of the men, Ranskahov screamed at him that he needed everyone.
- "We must go quickly!"
- ―Sergei to Vladimir Ranskahov
Sergei stayed by Vladimir Ranskahov's side as his army of soldiers prepared to go to war with Wilson Fisk. As Ranskahov was putting on his body armor, Sergei noticed that one of Madame Gao's blind workers had entered the facility. Sergei questioned whether or not they were expecting a delivery of heroin from Gao and quickly got his answer when the man held up a detonator. Sergei and Ranskahov ran for cover just as the bomb he was wearing exploded, killing every other man in the facility.
Barely surviving the fireball, Sergei carried Vladimir Ranskahov from the burning building to safety, but before they could escape, they were attacked by the Masked Man, who beat them both into submission. They were then interrupted by a team of corrupt police officers, led by Corbin, all of whom were working for Wilson Fisk. As the team attempted to arrest the three and execute them, the Man in the Mask broke free and fought the police; however in the chaos, Corbin was able to wound Ranskahov in the leg and kill Sergei with a bullet to the head.
- Beretta Px4 Storm: A handgun that Sergei carried while torturing Claire Temple inside the Veles Taxi Garage. Once the man in the mask arrived to rescue Temple, Sergei took the gun and tried to shoot at the masked man, but he ended up holding Temple at gunpoint in an attempt to escape. However, the masked man disarmed him and broke his arm before knocking him unconscious.
- Vladimir Ranskahov † - Employer
- Anatoly Ranskahov † - Employer
- Piotr †
- Madame Gao
- Turk Barrett