In just nine days, the film shot past the $312 million international total for Iron Man 2 in its entire theatrical run.

Among the overseas totals so far: $63.5 million in China, $42.6 million in South Korea, $38.3 million in Great Britain and $35.8 million in Mexico.

Domestically, Iron Man 3 far outpaced the franchise's first two movies. Iron Man launched the series with a $98.6 million domestic debut in 2008, while 2010's Iron Man 2 opened with $128.1 million.

The film also opened higher than last year's Batman finale The Dark Knight Rises ($160.9 million) and the biggest of the Spider-Man movies ($151.1 million for Spider-Man 3).

If Downey doesn't sign on for more, it would leave a gaping hole in the expanding superhero universe Marvel is taking to the big-screen.

"I honestly don't know how you can go on with that character without Downey," said Paul Dergarabedian, an analyst with box-office tracker Hollywood.com. "I think he's as important to this franchise and to Marvel as any actor is to any character."

Downey seems just as vital to The Avengers. That ensemble probably could thrive without him, given how the first film and previous solo superhero adventures have established a team that includes Chris Hemsworth's Thor, Chris Evans' Captain America, Scarlett Johansson's Black Widow and Mark Ruffalo's Hulk.

But without Downey, Marvel might have to settle for something less than the colossal $1.5 billion worldwide results for The Avengers.

"He's the spark that ignites all those characters, it seems," Dergarabedian said. "He's the lead guitarist, and they're just all kind of following him."

Before convincing reluctant Marvel executives that he was the man to put on the metal suit, Downey still was trying to live down drug addiction and jail time in his 20s and 30s that nearly ruined his career.

If you liked this article you might like

Market Selloff Survival Strategies: Cramer's 'Mad Money' Recap (Thurs 9/21/17)

Royal Caribbean Cruise Set to Sail Through Caribbean Hurricane Disasters?

Microsoft's New Xbox One X Shows It's Done Trying to Please Everyone

'The Handmaid's Tale' Emmy Win Is Really Big for Netflix

Stocks Dad Would Have Loved, And Why He Was Right