Robert Downey Jr. stars as the title character, alongside Antonio Banderas, Michael Sheen, Jim Broadbent, Jessie Buckley, Harry Collett, and Kasia Smutniak in live-action roles, with Emma Thompson, Rami Malek, John Cena, Kumail Nanjiani, Octavia Spencer, Tom Holland, Craig Robinson, Ralph Fiennes, Selena Gomez, and Marion Cotillard voicing an array of creatures.

The film underwent three weeks of reshoots in the spring of 2019, directed by Jonathan Liebesman and written by Chris McKay, after initial test screenings yielded poor results.

After his wife Lily dies at sea, Dolittle retreats from human society and only tends to animals at his sanctuary that Queen Victoria gifted him.

Years later, Tommy Stubbins, a young boy, accidentally wounds a red squirrel named Kevin while out with his hunter father.

To track down the fruit, Dolittle brings his expedition to Monteverde, ruled over by Lily's father King Rassouli, to recover her journal.

[11][12] In March, Kumail Nanjiani, Octavia Spencer, John Cena, Rami Malek, Craig Robinson, Marion Cotillard, Frances de la Tour and Carmen Ejogo all signed on for voice roles as well.

[3] Prior to this, Universal had turned towards Seth Rogen and Neighbors co-writer Brendan O'Brien to help add comedy to the film, but neither could remain committed to the project and dropped out.

[4] In January 2020, on Joe Rogan's podcast The Joe Rogan Experience, Downey Jr. discussed the inspiration for the Dr. Dolittle character in the film, which he said stemmed from a Welsh neo-pagan physician called William Price: "Same way I did with Iron Man... before I signed on, I was just googling 'weirdest Welsh doctor', I just wanted to think of, I don't want to just do another English accent.. so there was this guy called William Price, who's a nutty Welsh doctor, he was a neo-druidist, he believed that he could communicate with all nature and all that stuff, so I sent a picture of this wild looking guy wearing this kind of suit with stars on it and like a staff in his hand [to Gaghan]... and he goes, "That looks good to me" and I was like "great let's do this movie"".

[18] Music artist Sia performed a new song of hers, "Original", for the end credits, while Danny Elfman composed the film's score.

The site's critics consensus reads: "Dolittle may be enough to entertain very young viewers, but they deserve better than this rote adaptation's jumbled story and stale humor.

[23] Courtney Howard of Variety called the film a "frenetic, crass kids' flick" and wrote: "What should have been an awe-filled adventure quickly curdles into an awful one, thanks to a pedestrian formula and the filmmakers' fixation on fart jokes".

[33] Writing for The Hollywood Reporter, Todd McCarthy said: "From the very first scene, it's clear something is terribly off with this lavishly misbegotten attempt to repopularize an animal-loaded literary franchise that was born exactly a century ago.

The oddly diffident star and executive producer Robert Downey Jr. never finds the power-supplying third rail needed to energize a tale that fails to make a real case for being reinterpreted".

Mark Kermode derided the attempt, comparing it unfavourably with Welsh actor Michael Sheen's English accent, calling it "something from Mars" and suggesting the film had been heavily dubbed.

Simon Thompson praised the attempt, stating "it's a brave choice, I take my hat off to Robert Downey Jr. for going for it" and "as flawed as it is, it warmed the cockles of my heart to hear a Welsh accent in the cinema".

[38] Another Welsh reviewer said that appraisal of the accent "depends on how much love you have for him in attempting to do it in the first place", arguing that he had "clearly swotted up on the dialect, dropping in random phrases like "tidy" and "mun", along with "I'll be there in a minute now" and "twty down"".

[43] Robert Downey Jr. later referred to the movie as "a two-and-a-half-year wound of squandered opportunity", and noted that its troubled production and failure led to a major rethinking of his career and life.