Summer is traditionally the season in which movie studios release their most expensive – and potentially most lucrative – films to the public. While this year’s crop was certainly not devoid of its share of big-budget extravaganzas, the hottest months of 2007 established some intriguing big-screen trends.

Third Time’s Not a Charm

With several successful series scheduled to become trilogies, this summer seemed destined to break records left and right. However, while movies like Spider-man 3, Shrek the Third and Pirates of the Caribbean: At World’s End made plenty of money at the multiplexes, each of them earned less than their predecessors. Perhaps this disappointment has to do with word-of-mouth, as the audience and critical response to many of this summer’s “three-quels” was lukewarm at best. Ocean’s Thirteen and Rush Hour 3 continued this downward spiral, with only The Bourne Ultimatum able to achieve greater success than previous films in its series.

80s Nostalgia Reigns Supreme

The 80s came back in a big way this summer with the film adaptation of the classic Transformers cartoon. Despite mixed reviews, it became the season’s bona fide crowd pleaser as audiences relished the chance to see Optimus Prime and Megatron duke it out on the big screen. Live Free or Die Hard returned Bruce Willis to his signature role as John McClane, one of the most popular action heroes in movie history.

The film, in which McClane must thwart a technological terrorist, lured back much of the Die Hard fan base and became the highest-grossing film in the series despite a toned-down PG-13 rating.

Meanwhile, John Travolta led an all-star cast in Hairspray, the big-screen version of the musical based on the 1988 John Waters film. Since Hollywood has endless plans to reintroduce 1980s favorites, viewers should expect the retro resurrection to persist for a while.

Fantasy Soars (But Only if a Certain Boy Wizard Is Involved)

Despite the runaway success of The Lord of the Rings trilogy and The Chronicles of Narnia: The Lion, the Witch, and the Wardrobe, fantasy films continue to struggle at the box office. Stardust, which many critics likened to 1987’s classic fairy tale The Princess Bride, failed to achieve commercial success.

Unsurprisingly, Harry Potter and the Order of the Phoenix was the only fantasy film to reach blockbuster status this summer. Riding high on the Potter-mania surrounding the release of the seventh and final novel in the series, the film ranks as one of the year’s biggest money-makers, though it still failed to match the benchmark set by 2005’s Harry Potter and the Goblet of Fire.

R-Rated Comedy (But Not Horror) Still Sells

Since 2005’s summer smashes Wedding Crashers and The 40-Year-Old Virgin, smart R-rated comedies have become something of a sure thing. This summer’s Knocked Up proved that the market for these films is as strong as ever. Starring two up-and-coming leads, Seth Rogen and Grey’s Anatomy’s Katherine Heigl, the film emerged as one of the most lauded movies of the summer among critics and audiences alike. However, while Knocked Up re-affirmed the success of R-rated laughfests, the monumental failure of Hostel: Part II, the sequel to 2005’s gorefest, signaled that audiences who turned out for flicks like The Hills Have Eyes and Saw may have grown tired of over-the-top torture sequences and relentless carnage. Regardless, Saw IV hits theaters this October, hoping to return this particular subgenre to its prime.

Yellow Equals Green

Eighteen years after the series began, The Simpsons Movie finally saw the light of day in late July, with impressive results. Well on its way to earning $200 million at the domestic box office, the film successfully pleased hordes of Simpsons fans and earned new ones as well.

In addition, the film stood out among all the overblown and overwrought blockbusters as a foolproof example of summer entertainment at its finest. Hitting the perfect balance of intelligent humor and an exciting epic story, the yellow-skinned residents of Springfield transformed one of the most beloved television series of all time into an instant comedy classic.