It was fun because they pulled off the makeup acting so well.

There were some scenes that were difficult to act out. One such episode involves Corporal Kim Kwan-cheol (Kang Ha-kyung), known as the "Devil Corporal," who is reminded of his grandmother after tasting the nostalgic hamburger made by Kang Sung-jae. In Corporal Kim's flashback scene, Kang Sung-jae appears dressed as a grandmother and offers warm words along with the food. Park Ji-hoon reportedly said, "It was an emotional scene containing Private Kim Kwan-cheol's backstory, so I felt apologetic and cautious about appearing in grandmother makeup. I worried a lot that the emotion might be broken."