Star Robert Downey Jr. has revealed the full voice cast joining him for the action-adventure The Voyage of Doctor Dolittle. Antonio Banderas and Michael Sheen were previously announced as the live-action leads alongside Downey, with Tom Holland, Emma Thompson and Ralph Fiennes on board to voice three of the movie's computer animated animal characters. Harry Collett plays the key role of Tommy Stubbins, a boy who becomes Dolittle's assistant and accompanies him on his voyage. Stephen Gaghan (Syriana) directs from his own script.

The Doctor Dolittle book series, written by Hugh Lofting beginning in 1920, tells the story of a physician who one day discovers he can talk to animals. In all, 13 Dolittle books were published between 1920 and 1952. Hollywood first adapted the stories in a 1967 musical with Rex Harrison as the title character, surrounded by real-life animal co-stars. By the time of 1998's Dr. Dolittle starring Eddie Murphy, CGI was available to aid the living animal actors in the film. The new Dolittle adapts the second book in Lofting's series, an adventure story that expands on the first book, and features more mature subject matter.

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The new Doctor Dolittle will of course take full advantage of today's technology to create fully animated co-stars for Robert Downey Jr. And the movie's star has now revealed the list of actors who will voice all those animal characters. See his tweet with all the details below.

Joining previously revealed voice actors Holland, Thompson and Fiennes is an impressive list of thespians, including a couple of Oscar winners. Pop star Selena Gomez heads up the cast, together with Kumail Nanjiani, John Cena, Octavia Spencer and Marion Cotillard. Mr. Robot star Rami Malek also appears, with Craig Robinson, Carmen Ejogo and Frances De La Tour rounding out the cast. Downey's tweet also helpfully reveals the name and species of each animal character the above actors will voice. Downey's Avengers: Infinity War co-star Tom Holland gets to play Dr. Dolittle's own dog Jip, which makes for an interesting meta joke when you think about the relationship between Tony Stark and Peter Parker in the MCU.

Oscar-winner Emma Thompson meanwhile plays Dolittle's parrot Polynesia - oddly, the perfect role for Emma Thompson. In an example of on-the-nose casting, pro wrestler and recently announced Duke Nukem star Cena plays a polar bear. Rami Malek gets to play a gorilla named Chee Chee, which we assume is his actual identity and not an alter ego pushing him to perpetrate a massive hacking attack against the entire world's economic structure. The original book's most fanciful character, The Great Glass Sea Snail, does not appear in the rundown. Maybe a giant glass sea snail just doesn't need a voice? With the help of CGI wizardry, The Voyage of Doctor Dolittle should at the very least be the most visually impressive of all the Dolittle adaptations that have come along over the years.

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Source: Robert Downey Jr.