By R.T. Watson

U.S. movie theaters enjoyed their best few days since the pandemic shut down much of the economy, as the first major film in months opened with modest box-office returns.

Sci-fi spy film "Tenet," -- distributed by AT&T Inc.'s Warner Bros. studio -- grossed $20.2 million in the U.S. and Canada through the long holiday weekend, according to preliminary estimates.

Directed by Christopher Nolan and starring John David Washington, Robert Pattinson and Elizabeth Debicki, the $200 million film was regarded in Hollywood as having a solid chance of reviving the moribund theatrical business. Mr. Nolan's last movie, "Dunkirk," grossed $50.5 million in its opening weekend in 2017.

Movie theaters around the world had closed their doors as governments moved to contain the spread of the coronavirus; in the U.S., that happened in March. Hollywood's biggest studios canceled plans to release big-budget movies and almost overnight the few theaters still open lacked the high-profile films it takes to sell a significant number of tickets.

Theaters waited anxiously as Warner Bros. repeatedly changed its release plans for "Tenet" and public-health authorities shifted their guidelines for public gatherings. Walt Disney Co. canceled plans to release its live-action remake of "Mulan" in the U.S., opting instead to ship it directly to its Disney+ streaming service, where it also became available over the weekend. The company hasn't said how many viewers watched it, at a cost of around $30 on top of a monthly $6.99 subscription fee.

"We always knew this release plan would be a marathon not a sprint as we await openings in more markets and theaters," Warner Bros. said. The studio cautioned against judging "Tenet" against other film debuts, saying "any comparisons to the pre-Covid world would be inequitable and baseless."

Many nations have outpaced the U.S. in terms of reopening their economies and public spaces, so "Tenet" initially made its debut a week earlier in more than 40 international markets, where it made a total of $53 million in its opening weekend.

Major theater chains began reopening their U.S. locations last month, though they remained closed by government orders in several major population centers, including New York and California. Around two-thirds of domestic theaters have reopened, according to a recent estimate from Disney.

The movie earned another $58.1 million in overseas markets Friday through Sunday, according to Warner Bros., for a total $146.2 million globally. "Tenet" performed best in China, the world's second-largest theatrical market behind the U.S., where it made $30 million its first weekend, according to data provided by Comscore. China began reopening theaters in July.

Comscore analyst Paul Dergarabedian said it is nearly impossible to assess the performance of "Tenet," as "traditional metrics simply do not apply."

Pandemic-driven closures have obliterated the year's box-office returns. Heading into the weekend, with only four months remaining in 2020, domestic box-office revenue for the year so far stood at about $2 billion, according to Comscore data. Last year, theaters in the U.S. and Canada sold $11.4 billion of movie tickets.

Most U.S. movie theaters that have opened are operating at reduced capacity, meaning fewer people can attend screenings. To compensate, many theaters are showing "Tenet" on more screens than they normally would.

If California and New York allow theaters to reopen, it would almost certainly provide a boost for "Tenet." Metropolitan markets such as Los Angeles and New York City typically account for a significant share of domestic ticket sales.

Warner Bros. is also requiring some multiplexes to show "Tenet" for as long as 12 weeks in the hopes that more people will feel safe to return to cinemas in the coming weeks. The majority of theater chains require moviegoers to wear face masks.

Disney's "The New Mutants" ranked a distant second at the domestic box office, grossing $3.6 million over the Labor Day weekend, the studio estimated. Through the holiday weekend, the X-Men spinoff, which has received lackluster reviews from critics and audiences, grossed just $12.4 million in total after two weeks in North American theaters.

Disney had better luck abroad, where "Mulan" opened in smaller Asian markets where Disney+ isn't available. The movie topped the box office in Malaysia, Singapore and Thailand on its way to grossing $5.9 million internationally through Sunday. "Mulan" opens this coming weekend in China, where the legendary folk hero originates.