The Brain-Killer Affair - S1-E23
Continuity mistake: In the stairwell, Illya shoots the second Thrush gunman one time. When the man starts to fall, there are no holes or marks at all on his white jacket. A few seconds later, as he finishes falling down the stairs, three bullet holes suddenly appear in his coat, even though Illya only shot him once. (00:42:00)