Tom Cruise: winning. (Ian Gavan/Getty Images)

The No. 1 movie in America is “Sherlock Holmes: A Game of Shadows,” the Robert Downey Jr. vehicle that allowed him to reprise his role as the iconic detective and dress in drag to the tune of $40 million. (Well, dress in drag for part of the movie.)

But the real winner at the weekend box office? That was Tom Cruise, whose “Mission: Impossible — Ghost Protocol,” debuted in third place, right behind “Alvin and the Chipmunks: Chipwrecked.”

Wait, what? In what universe does being a runner-up to a Chipmunk movie sequel — or should I say squeakquel? — count as a win?

Allow me to explain.

Mission: Impossible — Ghost Protocol” made $13 million at the box office over the weekend, about as much as the lackluster “New Year’s Eve” brought in the weekend before. Here’s the difference: “Mission: Impossible” opened in very limited release, showing on only 425 screens across the country.

That means the per-screen average for the latest Ethan Hunt ad­ven­ture was a very impressive $30,588. That makes it the highest-grossing limited release of all time, according to Box Office Mojo. And that tells us a few things:

1. Imax ticket sales are helpful. The majority of the theaters showing “Ghost Protocol” screened the Imax version. Tickets for Imax movies cost more money. Which means that most of the revenue earned ($11 million worth, to be specific) came from the Imax side of the spectrum. So clearly there was interest in this one on the audience’s part, but paying a premium price to satisfy that curiosity certainly bumped up the box office numbers.

2. Positive reviews also are helpful. “Mission: Impossible — Ghost Protocol” earned stellar reviews from critics, including The Post’s Ann Hornaday; it boasts a 95 percent positive rating on Rotten Tomatoes. When you filter by top critics, that percentage jumps to 100. That may have motivated the fence-sitters to get their behinds into multiplex seats.

3. Batman can be helpful, too, but only a tiny bit.

The much-buzzed-about “Dark Knight Rises” prologue rolled in front of select screenings of “Ghost Protocol.” That probably didn’t account for a significant amount of box office dollars, but all the chatter about it might have pushed “Mission: Impossible” into the minds of moviegoers, whether they wanted a sneak peek at Bane or not.

4. This is good news for Jeremy Renner.

Renner has been making very smart choices about how to establish himself as an action star. First, he showed up as Hawkeye in “Thor,” a role he’ll play more prominently in “The Avengers.” He joined Cruise’s team in “Mission: Impossible,” where he’s poised to potentially inherit the franchise. And he’s (kind of) taking over for Matt Damon in the “Bourne” series. The performance of “Ghost Protocol,” assuming it holds up in wide release when it opens in more theaters Wednesday, suggests audiences are perfectly happy to see him handling suspenseful moments and loud explosions.

5. This is good news for Tom Cruise.

Cruise surrounded himself in “Ghost Protocol” with a strong supporting cast and a great director in Brad Bird. But the fact remains that “Mission: Impossible” is still thought of as a Cruise franchise. The initial success of the film in North American theaters, not to mention overseas, where it earned $68.2 million over the weekend, tells us that at almost 50, Cruise is still an action hero. Whether this sounds like awesome news or your worst nightmare is irrelevant. In Hollywood, all that matters is money. And Cruise’s latest attempt to bravely leap across very tall buildings made an impressive amount of money this weekend. If it continues to make more, that establishes that the man simultaneously beloved as Maverick and bashed for jumping on couches is still something very important: bankable.

Can Cruise rise above Lisbeth Salander and Matt Damon to make it to No. 1 next weekend? Vote in the poll below, following the list of the weekend’s top five films.

1. “Sherlock Homes: A Game of Shadows”: $40 million

2. “Alvin and the Chipmunks: Chipwrecked”: $23.5 million

3. “Mission: Impossible — Ghost Protocol”: $13 million

4. “New Year’s Eve”: $7.4 million

5. “The Sitter”: $4.4 million