It's summer, so it's Tentpole Time for the major Hollywood studios. One budget-buster that leaped onto the scene a few days ago, Transformers: The Last Knight, was the No. 1 performer at the box office this past weekend, as anticipated. Behind it, tied for No. 2, were the previous weekend's winner, Cars 3, and the durable superhero hit Wonder Woman. Third place belonged to seaborne thriller 47 Meters Down.

A franchise getting rusty?

Transformers: The Last Knight's winning debut, in which it booked an estimated $69.1 million in domestic ticket sales, would seem to be a triumph. But that's by far the weakest opening of any of the five entries in the long-running franchise from Viacom's (NASDAQ:VIA) (NASDAQ:VIAB) Paramount.

Transformers: The Last Knight.

Image source: Paramount Pictures (Viacom).

This is a bit alarming for Viacom, as Paramount really only has two big-ticket franchises these days -- Transformers and Star Trek. And Star Trek's returns are also diminishing; the series' three films have raked in progressively less at the box office during their theatrical runs, on the back of opening weekend performances that have steadily declined.

Luckily, Viacom/Paramount is distributing Transformers: The Last Knight in at least one very amenable foreign market. Chinese moviegoers somehow love the poorly reviewed film; it collected over $123 million in that country over the weekend. This formed the bulk of the movie's estimated $196 million in gross ticket sales abroad.

Still, the film's production budget is estimated at $217 million, so it probably has some way to go before it can post a meaningful return for Viacom.

The prospects are better for one of the No. 2s. Wonder Woman, of course, has been a wonder at the box office. In its third week of release, the film booked nearly $25.2 million in domestic ticket sales.

That's adding nicely to its cumulative gross, which now appears to be well on pace to be the highest out of the four DC Extended Universe movies from Time Warner's (NYSE:TWX.DL) Warner Bros. In its three weeks at the multiplex, Wonder Woman's take has exceeded $318 million, well within striking distance of its Warner stable mates Suicide Squad's just over $325 million, and the $330 million-plus of Batman v Superman.

The second No. 2, Cars 3 from Walt Disney's (NYSE:DIS) Pixar, also reaped just under $25.2 million domestically. This tally was 53% lower than the movie's opening weekend.

Although it hasn't been a smash hit abroad for Disney, bringing in an estimated $41.4 million during its run (compared to just under $100 million in this country), debuts in fresh foreign markets might help some. Later this summer, Disney will open it in nations such as the U.K., France, Germany, and Japan.

Finally, No. 3 47 Meters Down, released by privately held Entertainment Studios, collected around $7.4 million over the weekend. Now in its second week of release, the film's domestic "cume" -- the cumulative audience -- stands at over $24 million. It hasn't yet been released abroad. 

Coming attractions

The final June weekend will see the debuts of a clutch of new films. Representing the seemingly endless parade of sequels is the animated comedy Despicable Me 3 from Comcast's Universal. And a pair of new live-action comedies will open -- Warner releases The House and Gunpowder & Sky's The Little Hours.

There are also fresh horror and thriller offerings for fans of those genres. Everyone's favorite spooky Long Island house reveals its terrors for the umpteenth time in Amityville: The Awakening distributed by The Weinstein Company and its affiliate Dimension. Meanwhile, the action thriller Baby Driver, a Sony release directed by acclaimed British helmer Edgar Wright, could be an offbeat hit.  

Eric Volkman owns shares of Walt Disney. The Motley Fool owns shares of and recommends Walt Disney. The Motley Fool recommends Time Warner. The Motley Fool has a disclosure policy.