The filmmaker has been hired by Legendary Entertainment to serve behind the camera for the movie focusing on a new character in the Pokemon universe, Detective Pikachu, reported Deadline.
Letterman will direct the movie from a screenplay by Nicole Perlman ("Guardians of the Galaxy", "Thor") and Alex Hirsch ("Gravity Falls").
Details about the plot and supporting characters in the upcoming film are still scarce.
The video game, which was released earlier this year, follows Tim Goodman, a young boy who meets Pikachu in Rhyme City when he's searching for his missing father.
Nineteen animated films based on the property have been made with the first movie, "Pokemon: The First Movie: Mewtwo Strikes Back", released in 1998.