Critics have given Black Panther a 100% score on Rotten Tomatoes ahead of a campaign planned by trolls to flood the website with negative reviews.
Sixty-four critics' reviews have so far been counted on the movie ratings website, with an average rating of 8.6/10 giving it an overwhelmingly positive reception in the first days since the film's review embargo was lifted.
MetaCritic, which also aggregates reviews from around the internet, has given the film a score of 87.
Black Panther director Ryan Coogler had said that a Rotten Tomatoes score could be "an oversimplification of what critics are saying about a movie".
Expectations are high for Black Panther, Marvel's first film led by a black superhero. Opening weekend box office predictions stand at $150m (£107m) in the US alone.
However, an alt-right group called Down with Disney's Treatment of Franchises and Its Fanboys was gathering pace on Facebook before it was removed from the site. It planned to ruin the film's Rotten Tomatoes rating to "strike back" at Disney for "paying off the critics that hurt DC Comics on film and for other parties affected by them".
It is believed more than 4,000 people had signed up to the event before it was deleted.
Rotten Tomatoes is ready to delete any comments from users engaging in "hate speech" over Black Panther. A spokesperson told The Wrap: "We at Rotten Tomatoes are proud to have become a platform for passionate fans to debate and discuss entertainment and we take that responsibility seriously.
"While we respect our fans' diverse opinions, we do not condone hate speech. Our team of security, network and social experts continue to closely monitor our platforms and any users who engage in such activities will be blocked from our site and their comments removed as quickly as possible."
Some Reddit users falsely claimed that Rotten Tomatoes had said it would ban all negative reviews of the film. They slammed the site as "no longer a valid source of information or reviews" and said it was "committing suicide".
A Facebook spokesperson told CNN: "People often use Facebook to challenge ideas, institutions, and practices. Such discussion can promote a diversity of perspectives and greater understanding. However, we're opposed to hate speech and bullying, and don't allow either on our platform."