Your favorite animated friends are hitting the big screen in Pokémon: Detective Pikachu. JUSTICE SMITH (pictured) plays Tim Goodman. When his father goes missing, Tim goes looking for him. During the search, Tim meets Pikachu, his father’s Pokémon sidekick. Pikachu can talk, but only Tim can understand him. Together, they investigate the disappearance.

Acting alongside the computer-generated Pokémon characters was “hard but also a lot of fun,” Smith told TIME for Kids. “There were days on set when I was the only actor and the crew would watch while I talked to tennis balls [that stand in for animated creatures]. It was like playing pretend.”

Smith’s favorite Pokémon character as a kid was Totodile. “I always chose it as my starter Pokémon,” he says. The movie is in theaters May 10.