The upcoming live action-animation hybrid The Voyage of Doctor Dolittle just added even more big names to the project, Deadline reports. With Robert Downey Jr. already signed on as the film's title character, the actor took to Twitter today to announce the rest of the star-stacked cast. While actors like Antonio Banderas and Michael Sheen have live-action roles, many other boldface names will provide their voices for the animal characters in the film. Octavia Spencer, Kumail Nanjiani, Rami Malek and John Cena are just a few of the big names set to join the cast that already includes Ralph Fiennes, Emma Thompson, Tom Holland, and Selena Gomez.

"I am most pleased to announce the stellar voice cast joining me on #TheVoyageofDoctorDolittle," Downey Jr. tweeted.

The film, based on a series of Hugh Lofting children's books from the 1920s, is currently filming in London. Of course, this isn't the first time the Dr. Dolittle character has hit the big screen, with Eddie Murphy starring in the 1998 film Doctor Dolittle and its sequel in 2001. Those films would go on to gross $470 Million dollars at the worldwide box office, according to Variety.

The Voyage of Doctor Dolittle hits theaters on April 12, 2019.