Yuri Nikulin and Evgeny Morgunov initially refused to be part of the film as they felt the screenplay was too unrealistic. In the end, Gaidai convinced both actors to reprise their roles by agreeing to make some adjustments to the screenplay. It also took a long time to cast the role of Nina, with more than 500 screen tests completed before Natalya Varley was selected for the role. Because she worked as a circus tight rope walker prior to acting, she had an easier time with the stunt work and physicality required in the role. On the other hand, her relative lack of acting experience made the dialogue scenes more challenging for her.