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Yuriy Nikulin was the most frequent leading actor in Leonid Gaidai's films. He appeared in a total of 12 films by Gaidai, including the popular comedy series "Ivan Vasilievich: Back to the Future", "Carnival Night" and "The Diamond Arm". Nikulin's comedic timing and physical presence made him a natural for the roles of the bumbling but lovable protagonists in Gaidai's films.