COMIC book adventure“Iron Man”proved its mettle at the North America box office and topped expectations, kicking off the summer movie season with estimated weekend ticket sales of US$100.75 million and marking a commercial rebound for its star, Robert Downey Jr.

The tally far exceeded expectations of an opening in the US$70 million to US$80 million range for the three-day period beginning Friday.

Costing about US$150 million to make and US$75 million to market, the film is being closely watched as the first major release of the summer movie season.

Drawing largely favorable reviews,“Iron Man¡”stars Downey, 43, as billionaire industrialist and playboy Tony Stark, who wrestles with a mid-life crisis as he invents a high-tech suit of armor that transforms him into a superhero. The film was directed by Jon Favreau and co-stars Oscar winner Gwyneth Paltrow as Stark’s personal assistant, Pepper Potts.

For Downey, perhaps best known for his Oscar-nominated turn as Charlie Chaplin in 1992’s “Chaplin,” “Iron Man”easily marks his biggest picture yet, at least in commercial terms.

His promising career floundered in the 1990s when he succumbed to drug addiction that ultimately landed him in prison for a year. He was arrested twice more in the months following his August 2000 release but ultimately completed court-ordered rehab and has been on the comeback trail since.

His most recent films, such as“Zodiac,” “Fur”and “Good Night, and Good Luck,” were mostly acclaimed but largely flew under the mainstream radar.

The weekend’s only other new release, ¡°Made of Honor,¡± opened at No. 2 with US$15.5 million.

The romantic comedy, starring Patrick Dempsey, a.k.a. McDreamy from the hit ABC television drama “Grey’s Anatomy,”attracted a mostly female audience for its opening weekend.

Last weekend’s box office champ, the Tina Fey comedy“Baby Mama，” fell to No. 3 with US$10.33 million. (SD-Agencies)