Stop! Outsiders may not enter!Sergeant Plichko
Shadow of Chernobyl
He will refuse entrance to the player until the mission in Lab X-16 is completed. After the X-16 mission is completed, Barkeep will ask the Sergeant to allow the Marked One's entrance. If the player forces his way into Duty's base, or is discovered after sneaking onto it, Plichko and his team will open fire.