Geri plays white first and black second, taking off his glasses to become "Black Geri". Black Geri plays confidently and aggressively, while White Geri is nervous and makes mistakes. Soon White Geri is left with only his king against a full black army.
Unable to attack, White Geri fakes a heart attack and falls to the ground. While Black Geri is distracted with concern, White Geri turns the board around so that he now holds the winning pieces. He then checkmates Black Geri, who has to hand over the prize, a set of dentures. Geri happily puts them in.
The camera then zooms out to show one old man alone at the table in the empty park. This reframes the whole duel: the rival never existed, the trick was played on himself, and his "victory" is a private triumph over loneliness. All it takes to play chess alone is a competitive spirit.