For the box office, the Labor Day weekend is traditionally the bleakest holiday of the year, and this year is not likely to become an exception. (It also marks the official end of the summer movie season.) Of three new films that are opening wide, only one has been screened for critics. The three are Apollo 18 , a kind of Blair Witch Project set on the moon; Shark Night 3D , a PG-rated slasher movie with a shark playing the slasher; and the spy thriller The Debt (the only film that was reviewed; see separate item). None of the films is likely to earn more than about $12 million over the four days, most pundits agree, with a few suggesting that Apollo 18 may be the only newcomer that stands any chance of doing so. The Debt is expected to wind up with only about $6-8 million. Shark Night is likely to benefit from 3D surcharges. Once again The Help has become a wild-card entry. If it drops as little as it has over the last two outings, it could end up on top of the box office for a third week. Despite the dearth of appealing new fare, Daily Variety predicted on Thursday that enough tickets will be sold to lift the summer box office into record territory. It needs to take in more than $100 million to do so. The summer record was set in 2009 with $4.34 billion. As of Wednesday the domestic total stood at $4.24 billion, with admissions up about 2 percent over last year. Variety noted that for the first time the season's top five films were all sequels. "The summer frame was so thick with nonoriginal properties that only 6 of the 20 highest-grossing summer pics were not based on previous works," the trade paper observed.