"Prometheus" predecessor "Alien vs. Predator" was something dreamed up in comic books that eventually made its way to theaters. This weekend, the big-screen baddies who originated in the 1979 classic "Alien" will battle perhaps their most fearsome foe yet: animals. Furry, brightly colored, cartoon animals. With celebrity voices.

Whether the actual Xenomorphs seen in the movies that preceded Ridley Scott's new (sort-of) prequel show up onscreen won't be spoiled here. But one thing is for certain: "Prometheus" will face off against "Madagascar 3: Europe's Most Wanted" this weekend in a box-office race observers say will be extremely close.

"Our predictions are a $51 million opening for 'Prometheus' and a $49 million opening for 'Madagascar,' which is our way of saying it's a coin flip," Boxoffice.com editor Phil Contrino told MTV News. "We're giving the slight edge to 'Prometheus.' "

As of late Thursday, movie-ticket service Fandango reported that "Prometheus" led the weekend's new releases with 51 percent of the day's ticket sales, which lends support to Boxoffice.com's prediction. However, Jeff Bock, box-office analyst for Exhibitor Relations, put the slight advantage with the kid flick instead.

" 'Madagascar' may have the edge as it's already June and we're seeing the first real family film to hit multiplexes. It's opening in 1,000 more theaters than 'Prometheus.' It should be a close race though, with 'Prometheus' winning Friday and 'Madagascar 3' easily taking Saturday."

DreamWorks Animation's "Madagascar 3" reunites the voice cast of Ben Stiller, Chris Rock, David Schwimmer and Jada Pinkett Smith as Central Park Zoo animals looking to get back home. "Madagascar: Escape 2 Africa" opened at #1 with $63.1 million in 2008, eventually collecting $180 million domestically. The first film grossed $193 million. "Franchises aimed at children tend to lose steam in the third installment, at least domestically," said Contrino, who pointed to the latest "Alvin and the Chipmunks" movie as an example. The first made $217 million, the second $219 million, while "Chipwrecked" collected just $133 million late last year.

Originally conceived as a straight prequel to Scott's original "Alien" film, "Prometheus" evolved into something that takes place in the same universe but will explore its own story threads apart from the "Alien" franchise. Like the other films, however, it's a blend of dark themes, horror and action. It features strong female characters in prominent roles, alien baddies and a sinister futuristic corporation with less-than-altruistic motives. Noomi Rapace, Michael Fassbender and Guy Pearce co-star, along with Charlize Theron, who was in last weekend's #1 film, "Snow White and the Huntsman."

"Prometheus" carries an R rating, whereas "Madagascar" is PG. "If 'Prometheus' was rated PG-13, it would have a much better chance of taking the top spot," Bock said. "But both films should be able to open big on the same weekend [despite the ratings] as they are geared for very different demos."

Contrino said that the perceived commercial disadvantage of an R-rating is largely overblown. "The R-rating is not to be feared as much as it is. Whenever something comes along that's rated R, people panic. I really don't get it. Teens and children are not the only ones who buy tickets. In fact, adults are a more reliable target to go after because they are the decision makers. If an adult really doesn't want to see 'Madagascar 3,' then they'll find a way to wriggle out of it."

Both box-office experts agree that Fox's promotion of "Prometheus" has been respectably effective.

"I think 20th Century Fox has done an excellent job marketing 'Prometheus,' " Contrino said. "I expect that even people who aren't die-hard fans of the original films are going to show up. We track Facebook and Twitter and we saw big surges in activity for 'Prometheus' every time a trailer was released."

As much as the concept evolved away from films like "Alien: Resurrection" and the "AVP" movies, Bock said keeping some connection with the franchise has helped.

"Hits in the horror/sci-fi genre are far and few between. In fact, the 'Alien' franchise is really the only success story in this arena, so linking 'Prometheus' to 'Alien' with 'DNA' was exactly the right play by the studio," Bock said. "The marketing has been spine-tingling from a fan standpoint with all the moody imagery, ghostly glimpses of the mayhem and behind-the-scene trailers. It has many people making this film the centerpiece of their weekend. That's an event film, and that's what Fox has succeeded in creating. It remains to be seen if it connected to mainstream audiences, though. We'll find out the answer to that this weekend."

Recent weekend warriors "Snow White and the Huntsman" and "Men in Black 3" will, of course, have to settle for lower spots behind these two films. As for 2012's biggest box-office story thus far? "Marvel's The Avengers" may have to settle for fifth, Bock said, "but with $560 million and counting already, it has already earned its place as one of the biggest box-office hits of all time."

"It's going to have to scratch and claw its way to $600 million domestically, but I believe it still has a shot," Contrino said of the mighty superhero team-up film, which has made more than $1 billion worldwide. "The emergence of 'Prometheus' is going to kill any repeat viewings that might have happened this weekend."

Other films opening this weekend include Robert Pattinson's poorly reviewed "Bel Ami," which carried a 31 percent critical average on Rotten Tomatoes at press time; "Safety Not Guaranteed," from the producers of "Little Miss Sunshine"; Greta Gerwig's "Lola Versus"; and filmmaker Todd Solondz's "Dark Horse."

Check out everything we've got on "Prometheus" and "Madagascar 3: Europe's Most Wanted."

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