By Pamela McClintock, The Hollywood Reporter

Christopher Nolan’s Dunkirk stormed the box office with a better-than-expected $50.5 million domestic debut, the best opening in recent memory for a World War II film and a testament to the Nolan brand.

Still, Dunkirk will need sizeable staying power in order to recoup a net production budget of $100 million and a major marketing spend. Nolan made the movie for Warner Bros., his longtime partner and home of his blockbuster Dark Knight trilogy. Dunkirk, playing in 3,720 locations, no doubt benefited from a major push in Imax theaters, which delivered $11.7 million, or 23 percent of the total gross.

Heading into the weekend, many box-office pundits predicted that Dunkirk would have trouble crossing $40 million, considering its subject matter. They readily admit they were wrong. In addition to strong reviews, Dunkirk earned an A- CinemaScore from audiences. It skewed heavily male (60 percent), while 76 percent of all ticket buyers were over the age of 25.

Dunkirk opened on par with Nolan’s last film, Interstellar, which launched to nearly $50 million over the long Thanksgiving holiday in 2014, including $47.5 million for the three-day weekend. The Dark Knight Rises (2012) was his biggest opening ($160.9 million), followed by 2008’s The Dark Knight ($158.4 million), 2005’s Batman Begins ($73 million, including a three-day weekend of $48.7 million) and 2010’s Inception ($62.8 million).

Recounting one of World War II’s most famous battles, Dunkirk stars Fionn Whitehead, Mark Rylance, Kenneth Branagh, Cillian Murphy, Tom Hardy, Jack Lowden — and One Direction’s Harry Styles, who makes his acting debut in the movie, much to the delight of fans, who made their presence known at the film’s London and New York premieres.

Among other relatively recent World War II films, Angelina Jolie’s Unbroken debuted to $30.6 million in December 2014, while Fury launched to $23.7 million in November of that same year. Last year, Mel Gibson’s Hacksaw Ridge bowed to $15.2 million.

To this day, Steven Spielberg’s Saving Private Ryan (1998) remains the top-grossing World War II movie of all time domestically, earning $216.5 million (or $404.4 million when adjusting for inflation). The film opened to $31 million (or $57.6 million when accounting for inflation).

Overseas, Dunkirk is also making a major push.

Elsewhere at the North American box office, Universal’s Girls Trip broke the R-rated comedy curse in debuting to $30.4 million from 2,591 theaters. That’s the best showing so far this year for the genre, and helps to make up for summer flops Rough Night and The House. Like Dunkirk, Girls Tripcame in ahead of expectations.

Girls Trip — nabbing a coveted A+ CinemScore and placing a strong No. 2 — stars Regina Hall, Tiffany Haddish, Jada Pinkett Smith and Queen Latifah as lifelong friends who go to New Orleans for a raunchy weekend of fun. Malcolm D. Lee directed and produced alongside producer Will Packer.

The comedy was made for roughly $20 million, a modest number compared to Dunkirk and the weekend’s third new nationwide release, French filmmaker Luc Besson’s Valerian and the City of Thousand Planets.

Valerian, a sci-fi epic costing $180 million, crash-landed in the U.S. with $17 million from 3,553 theaters. STX Entertainment is releasing the movie in the U.S. via its partnership with Besson’s EuropaCorp, but doesn’t have any money in the film. Nor did STX pay for marketing, according to insiders.

Receiving a B- CinemaScore, Valerian is based on the French graphic novel series and stars Dane DeHaan and Cara Delevingne as celestial cops who must travel through space and time in order to save the universe.

Valerian came in No. 5 behind Dunkirk, Girls Trip and holdovers Spider-Man: Homecoming and War for the Planet of the Apes. Sony and Marvel’s Spider-Man pic took in an estimated $22 million in its third outing for a domestic total of $252 million. Matt Reeves’ Planet of the Apes threequel tumbled 64 percent in its second weekend to $20.4 million for a 10-day total of $97.8 million for 20th Century Fox.

Among other holdovers, Universal and Illumination’s Despicable Me 3 jumped the $200 million mark at the domestic box office, while Warner Bros.’ Wonder Woman has passed up Guardians of the Galaxy Vol. 2 ($386 million) to become the top-grossing film of summer and the second-biggest title of the year to date behind Beauty and the Beast with a total $389 million.

At the specialty box office, filmmaker Gillian Robespierra’s Landline opened to muted numbers for Amazon Studios and Magnolia. The indie film, which premiered at the 2017 Sundance Film Festival, grossed an estimated $52,000 from four theaters for a screen average of $13,000.

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