If "Mr. and Mrs. Smith" is a hit, odds are that won't be because of an overwhelming interest in the tale of married assassins who are oblivious to one another's history until they're hired to kill each other. Rather, audiences will go to the movie to see if they can catch a hint of the real-life heat between stars Brad Pitt and Angelina Jolie that by tabloid accounts led to the dissolution of Pitt's marriage to Jennifer Aniston.

Every once in a while a movie is overshadowed by events that took place behind the scenes while it was being made. Illicit affairs between actors; intense studio interference; tragic on-set accidents and/or deaths — for whatever reason, these films simply can't be taken wholly on their own merits: They become forever linked to the story behind the story.

In Hollywood's "Golden Age" during the '30s and '40s, tales of celebrity wrongdoing were mostly suppressed; studio publicists worked hard to keep the images of their stars squeaky clean, even if they often led lives that would've made Mötley Crüe blush. Even well into the 1950s, most actors' extracurricular activities (with the possible exception of Frank Sinatra's) stayed off the public's radar. It wasn't until the swingin' Kennedy era that what stars did off the set started to be honestly reported in the mainstream media.

Likewise, until the '60s, audiences weren't routinely informed — and likely didn't care — about how much money was spent on making a movie.

1963's "Cleopatra" set the precedent for behind-the-scenes media coverage in two ways. The first involved reports of the historical epic's astronomical budget, $44 million (including a then-record $1 million to Elizabeth Taylor for her portrayal of the doomed Egyptian queen), which, adjusted for inflation, comes out right around 300 mil — an amount that (rightly) still gives Hollywood the willies. And bear in mind, this was an era without ancillary income from home video or cable TV; 20th Century Fox expected to make back their money through theatrical receipts alone.

But the film's biggest headlines came from Taylor's affair with the movie's Mark Antony, Richard Burton. The two larger-than-life movie stars began a tempestuous relationship that not only mirrored that of the historical figures they were playing onscreen, but laid the groundwork for "news" stories of every offscreen hookup since, from Tom and Nicole to Bennifer (both of 'em). Whether because of the scandal or in spite of it, "Cleopatra" was not a box-office smash, and these days is better known for its excesses than its aesthetic merits (whatever they might be).

Yes, once upon a time, the money that studios spent on movies was their own business. Not anymore. These days, big budget extravaganzas seem on the verge of listing the accountant above the title. But the age of making a profit from home video and merchandising is a relatively new one. As recently as 20 years ago, a bloated budget could sink not only a film, but an entire studio.

Such was the case with 1981's "Heaven's Gate." Fresh off a multiple-Oscar win for "The Deer Hunter," including Best Picture and Best Director, Michael Cimino was given a blank check by United Artists to make his next film, a western about cattle wars in late 19th-century Wyoming. But Cimino's perfectionism and ego — two traits that had served the making of "The Deer Hunter" so well — caused tempers, patience, and (most famously) the budget and running-time for "Heaven's Gate" to all flare completely out of control. The four-and-a-half hour film ended up costing $40 million, and the studio refused to release it. Cimino agreed to trim more than two hours from the film, but it remained a convoluted, overly detailed mess, and the only people who went to see it were curiosity seekers. Ultimately, the movie nearly bankrupted United Artists, which was only saved by the release of the next James Bond film, "For Your Eyes Only." A detailed account of the whole debacle, "Final Cut," became a best-selling book by Steven Bach.

But at least nobody was killed during the making of "Heaven's Gate." (Well, no humans — the animal casualties were another story.) The 1983 big screen adaptation of "The Twilight Zone," on the other hand, became one of the most infamous releases in Hollywood history when three people died on the set. During the filming of a segment in which a racist man is forced to experience the effects of prejudice first-hand, a helicopter malfunctioned and crashed, killing star Vic Morrow and two children. Controversy boiled over when it came out that the event occurred after 2 a.m., when children are not legally allowed to work. To the shock of many, "The Twilight Zone" was released with the scene intact, omitting the crash, but still feeling a bit like the first mainstream snuff film. Director John Landis and four others were charged with involuntary manslaughter, but were acquitted of all charges.

An entirely different kind of controversy came to define the 1995 film, "Powder." Ostensibly a movie about being different, "Powder" stars Sean Patrick Flanery as Jeremy Reed, a hairless albino teen with telekinetic powers. He's (of course) ostracized by the community and comes to a tragic end that (of course) forces his tormenters and defenders alike to re-evaluate how they treat each other. But when it was made public that writer-director Victor Salva was a convicted child molester, people began reading all sorts of subtle and not-so-subtle messages into the childlike appearance of the movie's lead, and some saw the whole film as a rationalization for Salva's behavior. The controversy proved especially embarrassing for the movie's studio, Caravan Pictures, a subsidiary of the kid-friendly Walt Disney Corporation.

But the back story doesn't have to be tragic to overtake a movie. Sometimes the back story is all there is, as with the movies to come out of the "Project Greenlight" reality TV series. The show sponsors an Internet contest to find new screenwriters and directors, then documents the winners' struggles through an incredibly stressful version of on-the-job-training as they actually make a Miramax movie. As with all reality TV, the entertainment comes from watching other people make fools of themselves. So "Project Greenlight" is loaded with embarrassing footage of neophyte directors and writers thrown into the most ego-driven, self-important environment on Earth. The program goes to great lengths to avoid any spoilers concerning the movie being made, but by the time the finished film hits the theaters, anyone who's seen the show can't possibly view it objectively. Nobody wants to watch the "Making of" documentary before they see the film. Subsequently, the first two "Project Greenlight" films, "Stolen Summer" (2002) and "The Battle of Shaker Heights," (2003) stiffed at the box office. We'll have to wait for November to see if the same fate befalls the third film, a horror flick called "Feast."

As entertainment "news" continues to grow in our celebrity-obsessed culture, it becomes more and more unlikely that any movie is ever going to sneak into the multiplex without audiences knowing at least some cursory background information. And while it may make for a better informed filmgoer, does the back story of a film really matter? In the end, isn't it all about what we experience in the theater? Shouldn't we only care whether "Mr. and Mrs. Smith" is entertaining, rather than whether its stars were stealing smooches in their trailers?

Somewhere, Tom Cruise is sighing.

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