'Avengers: Endgame' opening: Fans remind each other #DontSpoilTheEndgame as epic film hits theaters

This post has no Avengers: Endgame spoilers. We promise!

With at least 8,000 showings around the country completely sold out, not every Marvel fan got to see Avengers: Endgame on opening night.

Some who did see the new film first watched all 21 Marvel Cinematic Universe films that came before it in an epic 3-day marathon.

RELATED: Everything to know before seeing Avengers: Endgame

Meanwhile on the internet, those who haven't seen it -- and also plenty who have -- are reminding other fans not to spoil the movie with the hashtag #DontSpoilTheEndgame.

It's a hashtag that Marvel itself has endorsed. In fact, the directors (brothers Joe and Anthony Russo) pleaded with movie-goers not to spoil it in an emotional letter earlier this month.

After the movie came out on Thursday night, some fans were reminding each other of the importance of taking the Russo's request seriously.

Some were sharing ways to have some spoiler-free Avengers fun on the internet.

And still others were sharing tips to avoid spoilers.

Endgame is expected to break box office records and has already done so in China. If you're looking for tickets, new showtimes are still being added.

Avengers: Endgame is in theaters now.

The Walt Disney Company is the parent company of Marvel and this station.

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