Vasili Sevchenko

Vasili Sevchenko is a character in Deus Ex: Human Revolution. He is one of the Sarif Industries scientists kidnapped by the Tyrants and forced to work for the Illuminati.

Background
He was one of the scientists at the Sarif Industries labs, working on the Typhoon Explosive System. At the night of attack by the Tyrants, he was telling General O'Neill about progress on the augmentation, and provided him with a demonstration of a very early version of it, with which O'Neill was impressed. He was presumed to have been killed during the Tyrants attack.

Much later Jensen discovers from Eliza Cassan that the Sarif scientists, including Sevchenko, were taken alive. Only one of them, however, can be tracked by their GPL implant - Sevchenko. Jensen infiltrates deep into Harvester territory in Heng Sha to look for Sevchenko, only to find Tong Si Hung wearing Sevchenko's augmented arm, with the implant in it. Tong informs Jensen that Sevchenko is unfortunately dead, and that he merely received the scientist's corpse from Belltower.

Tong agrees to help Jensen look for the remainder of the scientists, and directs him to the Belltower dock, where he stows aboard a ship. When the ship reaches its destination, Jensen awakens to find himself in the Omega Ranch facility. There he learns it was where the scientists from Sarif were imprisoned and forced to work for the Illuminati, including Sevchenko. While the other scientists put up little resistance, Sevchenko refused to cooperate and repeatedly came up with escape plans. Eventually he was deemed too troublesome by the facility officials and executed.

However, Sevchenko's death was not in vain. Before he was disposed of, he had created a virus to disable the facility's GPL signal tracker and jammer, which Jensen used to both free the other scientists and infiltrate deeper into the facility.