James Cameron's latest blockbuster "Avatar" has garnered universal praise for its eye-popping 3D special effects and the main question now is whether it can top his previous film "Titanic" as the highest-grossing film ever.
Another question, however, has surfaced in Russia. Did Cameron take the ideas of two brothers who wrote a series of science fiction novels in the Soviet Union in the 1960s?
Cameron and 20th Century Fox, the film's distributor, did not respond immediately to ABCNews.com's request for comment.
Critics say that Cameron outright copied some elements in "Avatar" from Arkady and Boris Strugatsky's 10-book "Noon Universe" series. Most notably the name of the lush, green planet where the film takes place, Pandora, which is the same name of the utopian setting the Strugatskys wrote about.
Then there's the name of the humanoids inhabiting Pandora: in "Avatar," they're the Na'vi. In "Noon Universe," the Nave.
"Cameron steals from the Strugatskys generously, using not only the planet Pandora which was invented by them," author and journalist Dmitry Bykov wrote in Russia's independent Novaya Gazeta newspaper. "The Na'vi are unequivocally reminiscent of the Nave."
Both "Avatar" and "Noon Universe" take place in the 22nd century, the Komsomolskaya Pravda newspaper noted in a full-page, side-by-side analysis. Both Pandoras are densely forested, and always warm and humid.
However, Komsomolskaya Pravda concludes that Cameron was "clearly not inspired by the Soviet works of science fiction," despite the similarities. Among the differences they point out are that the Na'vi are "Avatar"'s only civilization on Pandora, whereas the Nave in the books are one of two peoples on the planet. Living conditions on Earth are also depicted as being miserable in "Avatar," whereas in "Noon Universe" the planet prospers under communism.
Arkady Strugatsky passed away in 1991, but brother Boris has denied quotes attributed to him accusing Cameron of stealing ideas their bestselling books.
"I did not accuse the creators of the film 'Avatar' of plagiarism," Strugatsky wrote on his website, adding, however, that he has not seen the movie. All he knows, Strugatsky says, is that it involves "monsters on Pandora."
Film critic Kirill Rozlogov sympathizes with Cameron, saying that writers and filmmakers use many common elements when writing about the future.
"I think that in these books by the Strugatsky brothers you can find everything, including things that are in 'Avatar,'" he told ABC News.
Cameron has said that he wrote the first draft of the original screenplay in 1994. He revised the script for years and waited for the industry's technology to improve so he could shoot his masterpiece that has now brought in over $1.3 billion worldwide.