Japanese newcomer Rimu Kuwaki makes his debut as a savvy robot child surrogate.

Japanese auteur Hirokazu Koreeda is a regular at the Cannes Film Festival, largely returning to present films that deal with issues of life, death and parenting, both good and bad. This year his Competition entry Sheep in the Box, offers a sci-fi twist on those familiar themes, marking the acting debut of Kuwaki, who will turn 10 years old during the festival. Haruka Ayase and Daigo Yamamoto play his parents. And Kuwaki? “I play a humanoid who looks exactly like their child, who died in an accident,” he explains, “and continues living in their place.”

Kuwaki was chosen from more than 200 contenders, despite having next to no acting experience. “I’ve never really had any acting lessons — almost none, to be honest — but I have appeared in one drama series. The lines were basically just me being myself, so I’m not sure if you could really call it acting.”

Nevertheless, Kuwaki took to the challenge, and praises Koreeda for helping him ease into the role. “Director Koreeda Hirokazu is very kind,” he says. “He would encourage me by saying, ‘Let’s do our best,’ so any feelings of fear or embarrassment just disappear. Every time after shooting a take, he would also say to me, ‘That was really great,’ which made me so happy and motivated me to do my best again the next day. The atmosphere on set was fun and relaxed.”

Not every take was perfect, however. “Sometimes I got a bit too excited and started running around,” he recalls, “and I was told, ‘Robots aren’t supposed to sweat.’ And when I had a little bit food around my mouth, the crew said, ‘Robots don’t eat sweets, right?’ So I realized I had to be more careful.”

Kuwaki also learned a lot from his screen parents. “They’re kind, beautiful, and cool — I love them very much,” he says. Did he hang out with them to prepare for the role? “Yes, I did. We spent time together having meals, looking at photos of me as a baby, and even giving each other shoulder massages! It was a really fun time. As for what I learned, I was really moved by their facial expressions and movements during the acting, and it made my heart ache at times. It made me realize how amazing acting can be.”

Any plans to act again? “I like both watching movies and acting in them, and I hope to continue acting in the future. I’ve already told my family about my decision, and I’m going to do my best to appear in three more films.” And in the meantime, what else keeps him busy? “I like baseball, soccer, video games, golf, dancing and fishing. I’m currently practicing golf and dancing so I can get better at them.”