Box Office Preview: 'Iron Man 3' Could Cross $600 Million Worldwide by Sunday

Iron Man 3 Downey Paltrow - H 2013
Marvel Entertainment

Iron Man 3 Downey Paltrow - H 2013

The superhero tentpole debuts in North America on Thursday night after already earning $307.7 million worldwide.

Robert Downey Jr.'s superhero pic Iron Man 3 will be the master of the worldwide box office this weekend, with a good shot of grossing $600 million or more through Sunday.

The well-reviewed Disney and Marvel Studios tentpole launches at the North American box office on Thursday night after amassing $307.7 million in foreign grosses through Wednesday (the movie opened a week ago in a raft of markets).

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Prerelease tracking suggests that Iron Man 3 will open anywhere between $150 million and $175 million domestically (with tracking this big, it's hard to read the tea leaves), while it could score another $150 million internationally this weekend.

Overseas, Iron Man 3 is outpacing last year's Marvel blockbuster The Avengers, indicating that it is playing more like a sequel to that film versus Iron Man 2

In North America, it remains to be seen whether Iron Man 3 even has a shot of matching the record-breaking $207.4 million opening of Avengers, which featured Marvel's top superhero characters, including Downey's Iron Man.

Either way, the summer's first tentpole already is a hit, marking a key victory for director Shane Black, Marvel and Disney. Returning castmembers also include Gwyneth Paltrow and Don Cheadle.

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Even rival studios are hoping Iron Man 3 turns into a Goliath, saying it bodes well for the summer box office. Ticket sales year to date are running nearly 12 percent behind last year, causing concern.

No other wide release dared go up against Iron Man 3 this weekend, but a healthy crop of specialty films debut, hoping to woo adults. That includes Susanne Bier's Love Is All You Need, starring Pierce Brosnan and opening in four theaters in New York, Los Angeles and Washington, D.C.

Millennium's mob biopic The Iceman, starring Michael Shannon, also launches in a limited run. The indie distributor also opens the Julianne Moore-Steve Coogan drama What Maisie Knew.