Disney/Marvel's Avengers: Endgame, poised to be the hugest movie opening in history, has hit piracy networks - two days before its US premiere - with a copy evidently recorded in a Chinese movie theatre now circulating online.
Users in China began sharing a 1.2-gigabyte file of Avengers: Endgame on peer-to-peer piracy networks on Wednesday, piracy-news site TorrentFreak reported.
The pirated copy has since spread to English-language torrent networks, according to the report.
However, per TorrentFreak's report, the quality of the videocammed pirated copy is particularly bad.
"The image flickers constantly throughout," the site quoted a source as saying. "It's semi-rotated and is littered throughout with watermarks for a gambling site that spin around the screen."
The reported piracy of Avengers: Endgame comes after its debut on Wednesday in China, where it pulled in in more than $US100 million ($A143 million) and is set to be the biggest Hollywood movie ever in the country.
Avengers: Endgame is slated to hit theatres in North America on Friday.
A Disney representative did not respond to a request for comment on the report.
The illicit copy of Avengers: Endgame, as poor as the quality may be, comes after a spoiler-rich video clip, subtitled in Arabic, hit Twitter and Reddit last week, according to reports.
Joe and Anthony Russo, who directed the movie, last week urged fans in a Twitter post to not reveal Endgame spoilers.
"Remember, Thanos still demands your silence," they wrote, including the hashtag DontSpoilTheEndgame in the tweet.
Avengers: Endgame, which has clocked record ticket presales, is tracking for a phenomenal debut with a projected $US250 million-$US268 million ($A383 million-$A357 million) box office take in North America alone in the first three days of release.
© RAW 2019