https://www.cnet.com/news/detective-pikachu-trailer-turns-ryan-reynolds-into-a-pokemon/

Detective Pikachu is a spinoff from the Pokemon gaming franchise, which includes the Detective Pikachu game. 

"I think we all knew I'd wind up as a miniature detective repeatedly saying the same two words. Just didn't think it'd be this soon," Reynolds tweeted when sharing the trailer. He's referring to the conundrum that most people can only hear Pikachu saying "pika pika" when he tries to speak.