Vasiliy Fet

Fet notices before anyone else that something is wrong: the rats are leaving their hiding places in droves. He knows those animals better than anyone, and they only run like that when they sense danger. The trail leads him to Setrakian, and the exterminator joins up without asking for much explanation: to him, a vampire is just another pest to wipe out. He brings what the scientists lack: he knows New York's underground and kills pests without ceremony.

Fet's Brooklyn loft becomes the team's base, and he grows close to Dutch Velders, the hacker who joined the fight. While Setrakian chases the Lumen and Eph bets on science, Fet handles the muscle work: weapons, traps and hunts in the tunnels. At the battle of Red Hook, he holds the front line against the strigoi army, now thousands strong. Later, in the last episode, escapes by tugboat with Setrakian, Quinlan, Gus and Angel.

With New York under quarantine, Fet fights alongside Navy SEALs and becomes the team's soldier, more at home in a dark tunnel than in a lab. A nuclear bomb smuggled from Russia, found aboard the Aurora Cutlass, becomes the team's ace in the hole, and in the end lands in the wrong hands.

In the nuclear winter, with the strigoi walking by day, Fet sets out with Quinlan and Roman for another nuke. It is the team's last bet to end the Master, and Fet learns to fully trust a half-vampire. In the last episode, he plans to sacrifice himself by setting it off in a deep tunnel, but Zach is the one who triggers it. Five years later, with the world rebuilding, Fet is back to exterminating rats and reunites with Dutch.

Kevin Durand was a series regular for all 4 seasons.