'Avengers: Endgame' directors on when it's OK to finally talk spoilers online

Their answer might surprise you.

It's been a week since audiences were introduced to "Avengers: Endgame" and since then, the blockbuster film has broken all kinds of box office records.

Minor spoilers ahead for "Endgame."

The directors, Joe and Anthony Russo, stopped by "GMA" to talk about "Endgame," their favorite Avengers and when it's OK to finally talk spoilers online.

When asked about the eye-popping $1.2 billion the film made in its first weekend, Joe said, "These kinds of numbers are impossible to anticipate."

But they are just happy fans are connecting with the film.

"It speaks to the road the Marvel Cinematic Universe has traveled the past 10 years," Anthony added.

After the brothers were told about the massive Twitter numbers -- more than 50 million tweets so far -- they agreed that social media "drives interest in the film."

"But we hope they aren't talking spoilers," Joe said.

OK, so lay it on us, when is it finally good social etiquette to talk spoilers?

"I think it's Monday," Joe said about next week. "Give it two weekends."

As for what's next, the duo haven't thought ahead yet because "it is the end, our goal was to bring a closure ... and wrap up story on original six Avengers," Anthony said.

Who is their favorite?

Iron Man for Joe, Captain America for Anthony.

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