‘Avengers: Age of Ultron’: What will Week 2 hold for box-office heroes?

When Marvel’s “Avengers: Age of Ultron” opened in North America last weekend, superhero comrades Iron Man, Captain America and Thor faced competition from more than just a deranged android and his army of drones. They also fought for moviegoers’ attention — and their dollars — against the Floyd Mayweather-Manny Pacquiao boxing match, the Kentucky Derby and the NBA and NHL playoffs.

After the smoke cleared, “Ultron” had grossed $191.3 million, good for the second-best domestic debut ever but short of the $207.4-million haul of the original “Avengers” in 2012. The sequel had been projected to debut between $190 million and $230 million.

As “Ultron” approaches its second weekend with no “fight of the century” to contend with, few challengers at the multiplex (new openings include “Hot Pursuit” and “The D Train”), and an A grade from the polling firm CinemaScore (indicating positive word of mouth), the film’s box-office performance could shed some light on its long-term prospects.

According to projections, “Ultron” is expected to gross about $85 million in North America this weekend, a drop of about 55%. For comparison, the original “Avengers” dropped 50.3% its second weekend.

Conventional Hollywood wisdom for blockbuster movies has maintained that a drop of more than 50% is disappointing, and more than 60% is cause for concern. So should Marvel be disappointed, or perhaps even concerned? Maybe not.

Last summer saw an abundance of tent-pole movies with big openings but steep second-week drops, including “The Amazing Spider-Man 2” (61%), “Godzilla” (67%) and “X-Men: Days of Future Past” (64%). Whether the phenomenon has to do with the evanescent quality of contemporary blockbusters, the rise of high-quality home viewing or some other factor (or factors), the trend looks to be holding this year.

“Furious 7,” the highest-grossing 2015 release so far, declined 59.5% in its second weekend, and “Fifty Shades of Grey,” the year’s fourth-highest grosser, fell a vertiginous 73.9%.

More so than Mayweather, Pacquiao and even Ultron himself, the Avengers’ greatest challenge this weekend might well come from audiences looking for the next new thing to catch their fancy.

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