Is the rating a reason all by itself to avoid (or to pick up) a certain movie? (For example, would everyone who gambled on Will Ferrell's Semi-Pro in April have been better off if the movie had been rated a more teen-friendly PG-13?) And where can you find the latest news about film ratings? And of course, which genres' fortunes are most directly related to their rating? I'll also take a look at a few such summer films whose ratings will surely affect their performance — two that have already been rated, and two whose fates still hang in the balance. But first, I want everyone to know that this column has been screened and approved by ... er, someone.

Onward! When picking your slate, it's very important to keep ratings in mind. Think twice about choosing R-rated movies unless they are either a) very cheap (like The Strangers, which opens today, and has had the giveaway price tag of $2 for months), or b) an absolute sure thing. (Examples of such include The Passion of the Christ and The Matrix Reloaded, the two R-rated films with the biggest opening weekends ever.) That's not to imply that no R-rated movie is Fantasy Moguls viable. Players who reaped the rewards of American Gangster or 300 last year would surely argue otherwise. When you're considering a movie that carries an R, however, you should be cautious with it. In many cases, it's quite likely that R-rated films will make less money than their PG-13 counterparts. For example, Walk Hard: The Dewey Cox Story made just $18 million even in the plentiful holiday season, while Leatherheads, blessed with a more accessible PG-13, made $31 million even though it came out in the wasteland that is April.

Horror films and comedies are the types of movies most often at the mercy of the MPAA. That is to say, their success or failure sometimes has more to the rating and/or audience accessibility than the actual content of the film. For example, Shutter was objectively pretty terrible — just 9 percent Fresh at Rotten Tomatoes, and an IMDb User Rating of 4.7 — but it still brought in a surprisingly decent $25 million. Now try to envision the same result if it had been rated R. The total take may not have been half as much. If people under 17 can see your movie unattended, then your potential audience pool is logically that much bigger. This is especially observable when 14 year old girls take their cell phones to the theater, grab each other and scream when the movie is scary, text each other while the movie is in progress — despite the polite PSA during the pre-show telling you to turn off cell phones — and then ride home with their 14-year-old boyfriends, holding hands in the back seat of their mom's van. They go in droves; it's almost as scary as the movies themselves.

There are two recent and exemplary case studies. In terms of horror, consider the returns for both Prom Night ($43 million) and The Ruins ($17 million). As for comedy, look at the comparison between the aforementioned R-rated Semi-Pro, which limped to a $33 million take despite the "instant $100 million" presence of Ferrell, and the PG-13-rated Meet the Spartans, which raked in $38 million despite being arguably one of the worst movies of 2008 (2 percent — yes, 2 percent — Fresh at Rotten Tomatoes; IMDb number of 2.4). That's not a huge difference, but c'mon, almost anything has to perform better than a Jason Friedberg spoof movie, right? In both cases, the box office gross for the lower-earning film was dampened, at least in part, by the R rating.

So when does a rating provide the "kiss of death" for a film? This will usually happen only if the rating in question is an R (or, far less commonly, an NC-17 — given that some media outlets refuse to even advertise NC-17-rated films, that rating really is the kiss of death). It probably goes without saying that an R rating lowers the earnings ceiling for almost any film at least a little bit. If you've got an R-rated drama against, say, an animated family movie, you might not have as much to worry about. For example, American Gangster actually made more than Bee Movie on their shared opening weekend. Frankly, viewers would almost certainly have been more apt to disregard Gangster, a hard-edged, true-to-life examination of an enterprising New York druglord, if it hadn't been rated R. On the other hand, when you've got, say, an R-rated thriller against a PG-13 superhero flick, that's just a flop waiting to happen. I'd also say that an R rating for a film in December is basically a kiss of death as well. That's probably one explanation for why Walk Hard, despite generally good reviews, fared as poorly as it did, even with the name of super-producer Judd Apatow attached.

The Christmas season is driven by families; that's why Alvin and the Chipmunks and National Treasure: Book of Secrets were so successful. It's may also be, at least in part, why the Black Christmas remake made so little money ($16 million total) a few years ago. While we're on the subject of last winter, this theory even applies to I Am Legend. If that film had been rated R, it surely wouldn't have made as much as it did. While an R rating doesn't always mean your movie will tank, evaluate the surrounding competition and the film's own merits carefully before putting it on your slate.

Last winter also provided an even rarer example: an instance when a rating other than R was the kiss of death. Despite Christian outcry and some poor reviews, had The Golden Compass been rated PG, it probably would have fared much better than it did. In that scenario, it might have been the epic family event of the winter, as its marketers had plainly hoped. The PG-13 almost certainly closed the door to some parents, however, and probably prevented large groups of young children from being taken to (dropped off at?) a movie that, in most respects, probably would have pleased them far more than viewers of almost any other age. Thus, the door opened even wider for Alvin and the Chipmunks. In most cases, though, a PG-13 rating won't have negative consequences; the Harry Potter films are an example of how a PG-13 rating really hasn't stopped the cash train from chugging down the track.

The best place to find information on film ratings is the official MPAA website. There, you're getting the scoop straight from the horse's mouth, if you will, instead of relying on secondhand blog or forum posts to hear about ratings. They even give you the reasons for the ratings they've assigned. Usually, the reasons are pretty standard, but some humorous ones slip in occasionally. Some of my favorites: "quirky situations" (for Charlie and the Chocolate Factory), "brief smoking" (for The Water Horse: Legend of the Deep), "slime" (for Alien vs. Predator) and the explanatory addendum, given after a slew of other reasons, "all involving teens" (for Superbad). Ratings are archived, too (although the MPAA only began to append its explanations in 1990). You know, in case you were really curious to find out why, exactly, Batman Returns carried a PG-13. (For the record, it was all that "brooding, dark violence.")

You can also find early ratings information from rumor/breaking news sites like WorstPreviews, Rotten Tomatoes, and CinemaBlend. As they do with release dates, Box Office Mojo posts weekly updates (this week, ratings for The Incredible Hulk and WALL-E were posted), and as soon as new information becomes available, you can bet that a film's official website will be updated as well. You might also be able to guess when an R rating is imminent: with the re-emergence of red band trailers, if one is released — as recently happened with some Will Ferrell guy's big summer comedy  —  then you can probably bet that the film will eventually be rated R.

With that said, let's take a look at a handful of summer flicks that could live or die based on the effect of their ratings:

The Happening  — Now that it's been rated R (for "violent and disturbing images"), this one is basically dead in the water. M. Night Shyamalan's career has been going downhill since Signs, really  —  as I've mentioned before, he's been bouncing around between studios after disappointments The Village and Lady in the Water. Against The Incredible Hulk, it stands no chance, especially given the more friendly PG-13 rating Hulk has, and the general success Marvel Comics films have enjoyed recently. Had Universal settled for (or even aimed at) an R of their own with Hulk, this might be a different discussion, but an R-rating for his latest film is just about the last thing M. Night Shymasdlkfaldskjf44%#^lan needs right now. (Did I spelled that right? Of course I did.) His movies have found success because they attract that PG-13 horror crowd; without that, his potential audience diminishes greatly. Mark Wahlberg also isn't the biggest draw as a lead actor. Neither is Ed Norton, but the Hulk character is a bigger reason for people to go with the competition than anything M. Night could ever come up with. This is a disaster just waiting to, ahem, happen.

The Love Guru   —  By contrast, this Mike Myers-driven comedy recently earned a PG-13 (for "crude and sexual content throughout, language, some comic violence and drug references"), which makes it a potentially much bigger competitor for Get Smart, which has an all-access PG-13 (for "some rude humor, action violence and language") of its own. An R rating would have been the nail in the coffin, and I still don't think that The Love Guru will even approach the heights of Myers's Austin Powers films, but with a PG-13, Guru might put up more of a fight than you'd think. Since it's a summer flick, it'll have decent legs   —  another aspect of its performance that'll be helped by the rating. One thing's for certain: This movie isn't overvalued as far as Fantasy Moguls pricing goes. As I mentioned last week, it's a pretty good mid-range option in all formats. I'm not completely sold on it, and I don't think it's a must-have, but the PG-13 rating can only help matters.

The X-Files: I Want to Believe —  This film is, as of yet, unrated, but you've got to think it's between PG-13 and R. The last X-Files film was PG-13 (for "some intense violence and gore"), so that gives you a hint in one direction, and I Want to Believe's most direct competition, some flick with that wanker who belly-flopped in Walk Hard, just released a red-band "restricted" trailer, so it looks like that film is attempting to lock up the adult crowd. (Which, given the recent cinematic history of its two stars, might be deemed less than wise. There's been no final word from the MPAA here either, however, so stay tuned.) Clearly, PG-13 would be most helpful here, especially against potentially R-rated competition (a comedy, no less, something very susceptible, at least recently, to poor performance as a result of the rating). An R rating would be fairly damaging to I Want to Believe's Fantasy Moguls prospects, but against a doofus comedy with some Apatow fellow attached as producer, it wouldn't hurt as much since both major releases for the weekend would carry the same rating. Regardless, I don't see any way that 20th Century Fox lets this get into R territory —  that would tamp down the box office potential even more firmly than the formidable gap in time since the release of the last Files film and the end of the TV series already have.

The Mummy: Tomb of the Dragon Emperor —  Believe it or not, Brendan Fraser's return to mummy battling might come away with a PG rating, even though both previous films in the series were PG-13 (both primarily for "adventure violence"). There's some precedent for this: Fantastic Four: Rise of the Silver Surfer was rated PG after a PG-13 predecessor. I actually think that a PG would be more damaging to the movie (from a Moguls point of view), however, and a PG-13, in line with the others, would be more helpful. Call it Speed Racer Syndrome —  if a film is too bland or watered down in order to get that lower rating, it just comes off as a misfire. (That's not to say that Speed Racer was bland, but simply that, had the directors not wanted to pursue the family audience so much, the film might have had wider interest.) A PG-13 for Tomb of the Dragon Emperor would avoid the (possibly unfair) stigma that PG = family film, and also hold up well against the rest of August, where two of the biggest competitors will be R-rated: The Pineapple Express and Tropic Thunder. If I had to guess, I'd say it'll eventually grab a PG-13, mostly because the other two Mummy films were PG-13, and because director Rob Cohen (The Fast and the Furious, xXx, Stealth) has done pretty well with PG-13 in the past.

That's all for this week; I'll return next week with a rundown of June's studs and duds. Until then, good luck! Oh, and you'll be happy to know that I've just been given the final word about this week's column:

Mister Informative is considering an appeal, although he'd rather not have to cut any of his jokes about teenage girls, who really are a menace and should be confined to special theaters where they can't ruin the experience of other, more responsible filmgoers such as 10-year-old boys. Tell him what you think at misterinformative@gmail.com.