In the box-office battle of good versus evil (versus evil), two warring factions allied to secure the #1 spot.

"Alien Vs. Predator," which pits a group of Aliens against a crew of young Predators seeking a coming-of-age fight, easily won the #1 spot at the box office in its opening weekend, bringing in more than $38.2 million, according to early estimates.

The sci-fi action flick follows a group of scientists who, while on an archeological expedition in Antarctica, find themselves in the middle of an age-old battle between two legendary forces.

Losing the top spot to the battling creatures, "The Princess Diaries 2: Royal Engagement" bowed at #2 with more than $23 million in ticket sales. The film reconnects audiences with quirky princess Mia Thermopolis (Anne Hathaway) who finds out that she will take the throne earlier than expected and must marry immediately, before she can be crowned.

After knocking off his competition last week, Tom Cruise was taken down by gruesome creatures and a pretty princess. "Collateral," which bowed at #1 last week, dropped two spots to #3 with $16 million.

Animated action flick "Yu-Gi-Oh! The Movie" also debuted high, taking in more than $9.3 million to secure the #4 spot in its opening weekend.

"The Bourne Supremacy" fell two spots to #5 with $8.3 million. The total ticket sales so far for the action-thriller, which stars Matt Damon as a former CIA operative returning to his former life as an assassin in order to survive, are $139.4 million, making it the second-highest earner in the top 10, behind "Spider-Man 2."

M. Night Shyamalan's "The Village" fell back four spots, from #2 to #6, bringing in more than $7 million.

Rounding out the top 10 this week are "The Manchurian Candidate," which drops three notches from #4 to #7 with $6 million; "Little Black Book," which falls from #5 to #8 with $3.7 million; "I, Robot," which slips from #6 to #9 with more than $3.5 million; and "Spider-Man 2," which finally drops to the bottom of the top 10, sliding from #7 to #10 with $3.4 million.

Overall, ticket sales were down slightly from the corresponding weekend last year.

Next week, look for "Exorcist: The Beginning," "Without a Paddle" and "Open Water" to make appearances on the box office top 10.

Check out everything we've got on "Alien Vs. Predator."

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