It wasn't a great weekend for genre movies.
Shane Acker's animated film 9 took second place, with $10.9 million, in line with expectations. The film got an early start on the competition by opening on Wednesday, and its total stands at $15.3 million.
But other debuts tanked. Sorority Row debuted in sixth place, with $5.3 million, according to The Hollywood Reporter.
Kate Beckinsale's icy thriller Whiteout, meawhile, came in in seventh place, with just $5.1 million. Both films had been expected to open in the high-single-digit range.
The Final Destination, which topped the box office for the previous two weekends, fell to fifth place, with $5.5 million, taking its total to $58.3 million.
Quentin Tarantino's alternate-history movie Inglourious Basterds slipped one place to third place, with $6.5 million in its fourth weekend. The film has now earned $104.4 million.
Business usually drops sharply in the first weekend following the U.S. Labor Day holiday weekend, as children return to school and football season kicks in, the trade paper reported.