Not everybody is happy that Dwayne "The Rock" Johnson is set to play folklore legend John Henry. The actor posted a teaser for "John Henry and the Statesmen" on Instagram on Tuesday. Henry is an African-American folk hero who, as a steel driver, raced against a steam machine and won, giving up his life in the process.

Johnson wrote on Instagram that he's excited to play one of his "childhood heroes." In the upcoming Netflix film, he will lead an ensemble of "the most popular folklore figures and legends from different cultures around the world." He continued, "@NETFLIX is the perfect partner & platform to bring these global folklore icons to life. ... The legend of JOHN HENRY'S strength, endurance, dignity and cultural pride was instilled in my DNA at a very young age. My dad would sing 'Big John' to me every time he would put me to bed." He released a brief video teaser along with the announcement.

Jake Kasdan, who worked with Johnson on "Jumanji," directs. Johnson will produce the film, along with Kasdan, and Seven Bucks Productions' Dany Garcia and Hiram Garcia and Beau Flynn of FlynnPictureCo.

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Many Twitter users pointed out that Henry is portrayed in folklore as a dark-skinned black man. Johnson is mixed race; his father is black and his mother is Samoan. Johnson has played white, black and Pacific Islander characters in the past.

The dark skinned John Henry of Black folklore? (A double jab) Yeah that’s a no https://t.co/l2tB9rKy3L — George M Johnson (@IamGMJohnson) October 9, 2018

The Rock as John Henry...🧐🧐🧐 — Anathema BYOD (@CharlesPulliam) October 9, 2018

John Henry has always been depicted as dark-skinned but o k a y https://t.co/48Gq5KG9Vr — Ira (@ira) October 9, 2018

John Henry was a (likely unlawfully) imprisoned black man who was forced to work himself to death but OKAY. This @BackStoryRadio episode in part on him was very educational and heartbreaking. https://t.co/1eUJQpNKjQ — R. Eric Thomas (@oureric) October 9, 2018

John Henry is a dark skinned Black man. Here we go 🤦🏻‍♀️ https://t.co/56vm3vrdPc — Erin Floyd (@ErinMFloyd) October 9, 2018

Y'all I love the Dwayne Johnson but him playing John Henry has me in my feelings ... not in a good way — What can you add to me? 🇹🇹 (@BlkGrlsDontDate) October 9, 2018

I wish they had chosen someone else to play John Henry. https://t.co/7wkCEXZhEO — 𝗣𝗮𝗿𝗺𝗮𝗝𝗮𝘄𝗻𝗲𝘁𝘁𝗮 (@toberead75) October 9, 2018

Some even accused Johnson of playing up his black heritage when it's convenient.

Is he playing John Henry? Like he's ready to claim his blackness for a minute because it's convenient? https://t.co/JBHtZRznb4 — 🎃 🦇 🧛🏾‍♀️ 𝓑𝕝ᵉ𝒆𝐃 丨ᶰ ς𝓞𝕃𝑜ⓊŘ 🧛🏾‍♀️🦇 🎃 (@ReadInColour) October 9, 2018

This is what I'm asking. . . because. . . since when does The Rock actually claim being black?? https://t.co/Ab9vfFRAAD — Genie Lauren (@MoreAndAgain) October 9, 2018

In a GQ profile last year, Johnson said people most frequently guess that he is Greek.

In 2016, Zoe Saldana faced criticism for playing jazz legend Nina Simone, who was proud of her dark skin. Simone's own family told Saldana to "go to hell" on Twitter.