LOS ANGELES — "Barbie" has legs. Director Greta Gerwig 's film phenomenon remained a runaway No. 1 at the box office in its fourth week, bringing in $33.7 million, according to studio estimates Sunday.

The Margot Robbie-led and produced film from Warner Bros., still in 4,137 theaters, refused to drop off as most box-office toppers have this year, surpassing $500 million in North America overall a week after it crossed the $1 billion mark globally, a record for a female director.

The second half of the "Barbenheimer" duo, "Oppenheimer," returned to the No. 2 spot in its own fourth week after a week at No. 3 overall. The Christopher Nolan-directed film from Universal Pictures brought in $18.8 million from 3,761 locations for an overall domestic total of $264.3 million.

The top pair had thin competition. The week's top new release, Universal's "The Last Voyage of the Demeter," finished fifth with a $6.5 million opening weekend.

"Teenage Mutant Ninja Turtles: Mutant Mayhem," in its second week, earned $15.6 million domestically for third place, and the Jason Statham shark sequel, "Meg 2: The Trench," brought in $12.7 million, dropping from second to fifth in its second week in theaters.

“Barbie” is poised to become 2023’s top film. Its $526.3 million domestic total and $1.18 billion global bankroll currently sits second behind “The Super Mario Bros. Movie,” which earned $574.2 million North America, and $1.358 billion globally in the spring. It's also the second-highest grossing film in the history of “Warner Bros.,” behind only 2011’s “Harry Potter and the Deathly Hallows: Part 2.”

The sustained performance of the Mattel movie continues to flip the script on what had been a weak year in theaters, with major sequels underperforming including “Indiana Jones and the Dial of Destiny" and “Mission: Impossible — Dead Reckoning Part I,” which remained in the top 10 this week with $4.7 million.

“'Barbie' is as hot a commodity as it was in its first week. It's just ensconced at the No. 1 spot, and I don’t know if it’s going anywhere soon,” said Paul Dergarabedian, senior media analyst for Comscore. “And 'Oppenheimer' right there with it. They’re just drafting off each other in this box office NASCAR race.”

The midsummer “Barbenheimer” put the industry-wide summer total ahead of 2022. It was lagging behind just a month ago.

“If you think of what ‘Barbie’ and ‘Oppenheimer’ together — just those two movies — have contributed in these weekends at the box office, it’s really a staggering number," Dergarabedian said.

All movies combined this summer have earned $3.63 billion in North America. With significant releases remaining in August, including DC Comics' “Blue Beetle,” the video game adaptation “Gran Turismo,” and the Denzel Washington sequel “The Equalizer 3,” the box office has a chance of reaching the $4 billion that was considered a domestic benchmark for a strong summer before the pandemic.

Final domestic figures will be released Monday.

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