Over the past decade, Robert Downey Jr. has become practically synonymous with Iron Man, so it's perhaps no wonder the superstar would want to do something completely different for his first role after leaving the Marvel Cinematic Universe. He's always been a talented performer, and if his work in movies like Chaplin, Natural Born Killers or Sherlock Holmes are any indication, he’s capable of reinventing himself and his career. Unfortunately, Dolittle is unlikely to supplant his portrayal of Tony Stark in anyone's mind.

An uninspired, and uninspiring, fantasy, Dolittle attempts to appeal to all audiences and succeeds at pleasing none. The story, of course, centers around Downey’s eponymous Doctor, whose claim to fame is his ability to talk to animals. While that has kept the character in the public conscious since his literary debut in 1920, this latest take on him won’t help to burnish his legacy.

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The story hangs on an extremely thin thread. In Victorian-era England, Doctor Dolittle, who has spent seven years in isolation after losing his wife, is summoned to heal the ailing Queen (Jessie Buckley). When he arrives he realizes the only thing that will cure her is the fruit from a tree on an uncharted island, so Dolittle -- with his menagerie of animals and a young boy who insists on acting as his assistant (Harry Collett) -- sets off on the journey immediately.

Dolittle’s furry and feathered pals include a practical parrot (voiced by Emma Thompson), an anxious gorilla (Rami Malek), a polar bear who’s always cold (John Cena), a put-upon ostrich (Kumail Nanjiani) and an, ahem, daffy duck (Octavia Spencer). Along the way, the group goes up against a murderous pirate king (Antonio Banderas), a rival physician (Michael Sheen) and a scheming royal advisor (Jim Broadbent).

Given the impressive collection of talent assembled, which also includes voice performances by Tom Holland, Selena Gomez, Craig Robinson and Marion Cotillard, it’s easy to assume there must be something worth watching here. And while there’s nothing egregiously wrong with Dolittle, even its best bits are only middling.

Red flags popped up more than a year ago when the film was delayed from April 2019 until early this year. It was also reported the film underwent extensive reshoots. Now, it’s not at all unusual for a production, especially an effects-heavy extravaganza like Dolittle, to undergo reshoots. In this case, however, two other directors, Chris McKay (The LEGO Batman Movie) and Jonathan Liebesman (Teenage Mutant Ninja Turtles) were brought on to oversee the additional photography. While Stephen Gaghan retains sole director credit, the extra footage doesn’t appear to have fixed what was broken.

Gaghan, known for films like Syriana and Traffic, was always an odd fit for Dolittle (he also wrote the screenplay, with Dan Gregor and Doug Mand, from a story by Thomas Shepherd), and the movie has some glaring tonal challenges. There’s potty humor and slapstick that seem designed to amuse children, and then periodic references to movies like The Godfather and Back to the Future are mined for adult laughs. There’s also an extended sequence featuring a tiger with mental issues (Ralph Fiennes) that’s meant to be funny but ultimately comes across as sad and ill-conceived.

In addition, the movie relies on Dolittle’s grief over his dead wife to give him depth, but outside of that and his well-known ability to talk to animals, there’s very little to him. Downey’s performance feels routine and lacks the spark he often brings to roles. Plus, the accent he uses, which according to the production notes is supposed to Welsh, is inconsistent and puzzling.

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On the other hand, Rami Malek and Craig Robinson (the latter as a squirrel swept up in the adventure that periodically comments on the inanity of it all) make the animals they voice appealing. Best of all is Emma Thompson as the parrot who acts as the story's voice of reason. Thompson’s vocals help to ground this otherwise-weightless film.

This isn’t enough to recommend Dolittle, however. Not amusing enough to be a comedy nor weighty enough to be a drama, it's unlikely to truly entertain either kids or adults. It’s forgettable nonsense that doesn’t benefit from Downey’s usual charisma. Hopefully, the former Iron Man’s next role will be more engaging both for the sake of his legions of fans and the actor himself.

Directed by Stephen Gaghan, Dolittle stars Robert Downey Jr., Tom Holland, Jim Broadbent, Harry Collett, Emma Thompson, Selena Gomez, Craig Robinson, Rami Malek, Octavia Spencer, Ralph Fiennes, Kumail Nanjiani, John Cena, Antonio Banderas and Michael Sheen. The film is scheduled to hit theaters on Jan. 17, 2020.

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