Continuity mistake: When the 'good' Geri fakes a heart attack, a black knight can be seen standing on the edge of the board, right on the same diagonal as a black bishop. After the 'good' Geri falls to the ground, you can see that the black knight has moved. (00:02:58)
Deliberate mistake: During the game, you can see a hand that supposedly belongs to the 'evil' Geri and the 'good' Geri in the background, even though there is only one Geri in reality. This also happens with the laughs of 'evil' Geri. (00:02:24)
Continuity mistake: On his third move, the 'good' Geri moves his king's bishop to the third rank (one rank ahead of B2's pawn). After the 'evil' Geri captures the knight on h3, the white king's bishop is now on the second rank. Two shots later, the bishop is now on the first rank. (00:01:54)
Continuity mistake: Geri (with glasses) knocks off the box of chess pieces after faking a heart attack, but when the camera pulls back at the end of the movie, you can see there is no chess box or pieces on the ground.
