The movies might have been packed with explosions, but the summer box office ended with more of a whimper. Gross domestic ticket revenue peaked at $4.05 billion to end the Labor Day weekend down 15% from $4.75 billion a year earlier. For the first time since 2001, no single summer hit crossed the $300 million mark, unusual for a season in which studios stuff their big-budget, big-returns tent-pole films. Which studio released the biggest hit? Which suffered the biggest dud? And which generated the most from this limp summer haul?