Georgi Luchkov

Georgi Luchkov is a Russian agent working for KGB.

The Avengers
Georgi Luchkov tied the Black Widow to a chair and was interrogating her for information.Then one of his henchmen's phone rang claiming it was for Natasha, It was revealed to be Agent Coulson. Whilst talking to Coulson Natasha reveals she was actually extracting information from Luchkov. When Coulson informs her that Barton has been compromised she signals for Luchkov to take the phone then kicks him in the knees before eliminating the henchmen and breaking free from her restraints. She then drops Luchkov down a hole, left suspended by a chain around his ankle.

Trivia

 * In the comics, Luchkov is a former Russian KGB agent and is an enemy of the Black Widow, this is reflected within The Avengers.