Today, big-budget movies are as much a summer tradition as BBQs and beach flings. But things weren’t always this way. Much like Hollywood itself—and its surgically-enhanced denizens—the “summer blockbuster” is a manmade phenomenon. And one that occurred accidentally at that, with the release of Jaws in the summer of 1975 (though some may prefer the word “serendipitously” to “accidentally”).

In the nearly 40 years since, each summer an onslaught of big-budget movies make their debut, each one hoping to be the next great success story. But as The Lone Ranger reminds us, even a film that is tailor-made for mass consumption can’t be guaranteed an audience. “If you build it, they will come,” may have been true for Kevin Costner and his Field of Dreams, but it's only wishful thinking on the part of studio executives.

With the summer movie season now in full swing, and Guillermo del Toro’s Pacific Rim ready to see what kind of mega-robot magic it can work on the box office this weekend, we’re going all the way back to 1975 to retrace The Evolution of the Summer Blockbuster.

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