Box Office Preview: 'Apollo 18,' 'Shark Night 3D' Try to Knock Off 'The Help'

"Apollo 18," left, and "Shark Night 3D"

The Helen Mirren movie "The Debt" also is new in theaters.

Summer ends with a fright fest at the domestic box office as found-footage horror pic Apollo 18 and Shark Night 3D hit theaters Friday. The big question: Will The Help be unseated from her top perch?

Labor Day is always a popular time for genre fare that appeals to younger moviegoers looking for something to do over the long weekend. In general, the holiday isn't known for producing big opening grosses.

Focus Features will take a different approach and try to entice adults with Helen Mirren drama-thriller The Debt, which opened Wednesday to a strong $970,532, slightly better than the first day gross for Focus' 2005 adult hit The Constant Gardener, which also opened on the Wednesday before Labor Day weekend.

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From the Weinstein Co./Dimension Films, the micro-budgeted Apollo 18 was produced by Timur Bekmambetov and Ron Schmidt and directed by Gonzalo Lopez-Gallego. The project is impressive for coming together in less than a year; the Weinstein Co. and Bekmambetov teamed up last fall to announce the movie to foreign buyers at the American Film Market.

Apollo 18 is scoring impressive interest among men of all ages, meaning it won't have to rely entirely on younger consumers.

Tracking suggests that Apollo 18 could score a four-day gross of $11 million to $14 million; it will need to do on the higher end to beat The Help, which could earn as much as $12.5 million.

The Debtcould open as high as $11 million, likely followed by Shark Night with $8 to $10 million.

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Box office observers caution the order could easily change.

Costing only $5 million to produce, Apollo 18 is bound to be a financial win for the Weinstein Co. and Dimension if it performs as expected.

Set in December 1974 and shot in a mockumentary style, the movie shows the final footage from a doomed moon mission that was covered up by the government after American astronauts were attacked by parasitic life forms on the moon.

Shark Night 3D, from Sierra/Affinity and Incentive Filmed Entertainment, is appealing heavily to young females. Relativity Media, which is releasing the film, put up all marketing costs in the U.S. (E1 Entertainment is releasing the pic in Canada). Directed by David R. Ellis (The Final Destination), Shark Night revolves around seven college friends from Tulane University who spend a weekend on Lake Pontchartrain -- only to find themselves being attacked by salt-water sharks.

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Shark Night was produced by Chris Briggs, Mike Fleiss and Lynette Howell. The film's budget was under $30 million after Louisiana tax rebates, while the filmmaker's exposure was further minimized through foreign presales.

Shark Night opens in Russia this weekend, where there is a strong appetite for 3D fare.