[stldygig] Casually making the winning chess move

Two ancillary characters are engaged in deep thought over a chess game.   A main character shows up and rudely but casually reaches in and makes the winning move, establishing how intelligent the character is. The opponent immediate resigns by tipping over his king, because that's the way chess resignation always happens in movies.

Let the position on the board be from one of those monstrously long computer-generated tablebase endgames, often with unique winning moves that defy any sort of mortal logic.