The Illumination Entertainment and Universal Pictures film cost only $75 million to produce, and it features the voices of comedians like Louis C.K. and Kevin Hart. "Pets" has been warmly received by critics and audiences, who gave the film a promising A- CinemaScore.

Going into the weekend, analysts predicted it would earn only around $70 million, which would still have been a big success.

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Not adjusting for inflation, "Pets" earned the title of best opening ever for an original animated property. The previous record-holder was Disney and Pixar's "Inside Out," which opened to $90.4 million last year.

It's a big moment for Illumination Entertainment — the shop behind the hugely successful "Despicable Me" series and "Minions." The company is not quite Pixar yet, but it's working toward that sort of recognition.

"Illumination has been building a consistency of vision, and now they have become what every studio covets — a draw," said Paul Dergarabedian, senior media analyst for box office tracker comScore. "They're building that brand reputation with every movie."

The main draw, though, was likely in the simple and appealing premise: What do your pets do when you're not around?

"I think this movie resonates among all people," said Nick Carpou, Universal's president of domestic distribution. "It's a very charming way in for everyone to have fun with the concept of imagining their pets that way."

"Pets" effectively unseated "Finding Dory" from its three-week run in first place. The little blue fish actually fell to third place with $20.4 million, behind "The Legend of Tarzan" which took in $20.6 million in its second weekend in theaters.

Even with the drop, "Dory" this weekend surpassed "Captain America: Civil War" to become the top film of 2016 domestically, with its $423 million in grosses. It helped push The Walt Disney Studios to reach $5 billion globally in record time. Much of that was propelled by the success of its family fare including "The Jungle Book."

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"Family films have generated so much money this year," Dergarabedian said. "That's an audience who is always looking for content in a world filled with options for entertainment."

While Disney is celebrating its overall box office, there is one dud on the books. The studio's "The BFG" fell a giant 60 percent in its second weekend. The movie, which cost around $140 million to make, has earned a dismal $38.7 million to date.

There were also a fair number of adults looking for something new to see this weekend without the kids, helping the raunchy R-rated comedy "Mike and Dave Need Wedding Dates" surpass expectations with an estimated $16.6 million for a fourth-place debut. The film, distributed by 20th Century Fox, cost $33 million to make, and stars Zac Efron, Adam Devine, Aubrey Plaza and Anna Kendrick.

"The Purge: Election Year" rounded out the top five with $11.7 million.

The year is still up 3 percent from last summer, despite a string of underperformers lately. But there are still some would-be blockbusters on the horizon, including the new "Ghostbusters," which opens next weekend.

"The hope is that the momentum created by 'The Secret Life of Pets' will carry over to 'Ghostbusters,' 'Jason Bourne' and 'Suicide Squad,'" Dergarbedian said. "We're running out of track. It's almost the end of summer, and there's a lot of ground to make up, but one movie can make all the difference."

Estimated ticket sales for Friday through Sunday at U.S. and Canadian theaters, according to comScore. Where available, the latest international numbers for Friday through Sunday are also included. Final domestic figures will be released Monday.

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1."The Secret Life of Pets," $103.2 million ($7.8 million international).

2."The Legend of Tarzan," $20.6 million ($27 million international).

3."Finding Dory," $20.4 million ($29.7 million international).

4."Mike and Dave Need Wedding Dates," $16.6 million ($3.6 million international).

5."The Purge: Election Year," $11.7 million ($2 million international).

6."Central Intelligence," $8.1 million ($9.8 million international).

7."Independence Day: Resurgence," $7.7 million ($21.5 million international).

8. "The BFG," $7.6 million ($4.6 million international).

9."The Shallows," $4.8 million ($2.3 million international).

10."Sultan," $2.2 million ($18.2 million international).

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