10 Lessons from the 2009 Box Office

Hollywood can read numbers, and they say that audiences favor the familiar. Seven of the top 10 summer films were either sequels (Transformers 2, Harry Potter 6, Ice Age 3, Night at the Museum 2 and the Da Vinci Code successor Angels & Demons) or prequels (Star Trek, Wolverine). Only the Pixar fantasy Up and the two comedies, The Hangover and The Proposal, were in any way new ideas. And when an action movie, of whatever provenance, opens big, there's immediate talk of franchising: a sequel to District 9, a prequel to Inglourious Basterds. Right now, some screenwriter is surely trying to figure how to reconvene the Hangover gang or pry Sandra Bullock and Ryan Reynolds apart so that one of them can make another reluctant proposal.

It's all part of the industry's grand scheme to create or sustain properties that, every few years, will earn a bundle — essentially, to take the guesswork out of moviemaking. Also the ornery inspiration, and the naysaying of critics. Michael Bay's Transformers movies usually get scathing reviews, but Hollywood wishes there were 500 Bays of summer.

See pictures of the Harry Potter cast growing up.