Recorded in London last autumn after seeing footage of the documentary, Meghan's new show will start streaming on Disney+ on April 3.
The doco follows African elephant Shani and her son Jomo as they are led by their matriarch, Gaia, across the Kalahari Desert.
Both British and US press have been consistent in their reviews, with critics giving the show a very average three stars. While they praise its stunning cinematography, Meghan's voiceover has been dubbed as pretty 'meh'.
"For her part, Markle's delivery of the commentary is wholesome and over-eager to please," added Empire's Ian Freer, who gave the film three stars.
He said that Meghan "just about stays the right side of annoying".
The Times (two stars): "Meghan Markle is swapping pomp and circumstance for schmaltz and cheesiness... The sense of performance, though, often feels overegged."
The Times's Ed Potton (two stars): "Meghan is swapping pomp and circumstance for schmaltz and cheesiness", adding: "The departing Duchess of Sussex narrates Disney's tale of a herd of elephants crossing the Kalahari Desert from the Okavango delta to the Zambezi River, and boy does she lay it on thick."