After beating expectations (and last year's grosses) for four consecutive weekends, overall box office returns were generally disappointing this weekend, as old films slipped and new ones failed to make much of an impact. Though it kept a firm grip on the number one slot, Flightplan slipped 30 percent from last weekend, to gross just $15 million in this frame. It was still enough to hold off all comers new and old. Second place went to Joss Whedon's Serenity, which earned a $10.1 million on about 2,200 screens, and Tim Burton's The Corpse Bride slipped to third place with $9.8 million, Meanwhile, David Cronenberg's A History of Violence expanded to 1,300 screens and shot up to the number four spot with $8.2 million, easily beating newcomers such as Into the Blue (5th place with $7 million) and The Greatest Game Ever Played (9th place, $3.75 million). More numbers after the jump.