Semyon was a Russian Mafia member.
Semyon wore a cologne that was very strong. As he was being tended to by Claire Temple, Daredevil smelled the cologne of Semyon as he entered the building where Temple lived. Semyon knocked on many doors, in his disguise of a police detective, asking the tenants if they had any information about a masked man who robbed a bodega; in reality, Semyon sought the masked man because he was disrupting the criminal activities of Vladimir and Anatoly Ranskahov.
Semyon knocked on the door of Claire Temple's Apartment; Claire Temple did not answer until the Masked Man had a chance to hide. Seymon asked Temple if she had seen a masked man and told his story about the theft at the bodega; Temple said she knew or heard nothing and closed the door. Semyon began running down the stairs, speaking Russian on the phone.
The masked man realized that Seymon did not believe Temple. He then dropped a fire extinguisher on his head, knocking him unconscious.
The Masked Man and Santino took Semyon to the roof of the building and tied him up. Here he hung unconscious for multiple minutes, while Claire Temple and Murdock discussed why she helped him. Claire Temple was given a white mask to hide her face from Semyon.
Semyon awakened and noticed the masked man and a women wearing a white mask standing in front of him. He was told that he had to answer some questions and that every lie he gave would be noticed. Even though he was warned he still answered the first question with a lie, for which he received a punch. He then answered the next few questions with the truth, for which he still received a punch. After finishing his story, he pushed Murdock to keep on hitting him, saying that he would just be replaced if he dies. Before Murdock could continue beating him, Temple gave Murdock advice to stab him in trigeminal nerve.
After stabbing Semyon, Murdock placed Semyon on the edge of the roof. This scared him enough to finally reveal the location of the boy they had kidnapped. He then started to laugh, taunting Murdock by telling him that the Russians would be waiting for him and kill both him and the kid. This angered Murdock enough to push Semyon from the roof. Semyon landed in the dumpster below, severely injured, but not dead.
Coma and Death
Semyon laid in a coma in a hospital until awakened by Vladimir and Anatoly Ranskahov by a shot of epinephrine. Upon awakening, Semyon was asked what he knew about the masked man; he revealed the location of Claire Temple's Apartment to which Sergei was sent. He then breathed his last after giving that information.