there is one movie about chess, the guy challenges a chess grandmaster and the rules are if he wins or there is a draw he takes a pot of money and if he loses the grandmaster takes a prize.
they play by correspondence. the guy wins prize once, twice and then he loses and there is a draw or something like that and in the and of story there is revealed that he was playing with other grandmaster and sending responses to first one and from first one to second one so grandmasters were actually playing against each other.
Do you know that from any movie? i wonder if this movie theme was used often