The student wizard is back, this time for a summer outing. Regardless of the season, Time Warner (NYSE:TWX) knows that having the Harry Potter film franchise under its aegis is as good as employing a crack alchemist.

That other little fantasy series, the Lord of the Rings trilogy, took care of the 2003 holiday box office for Time Warner, producing a wealth of ticket sales and merchandise flow. It's up to Potter now, since Rings is pretty much done in terms of theatrical product (unless they figure a way around that -- Frodo in the City?). Harry Potter and the Prisoner of Azkaban, based on the tome by J.K. Rowling, took in $93.7 million last weekend for the domestic box office. That's on par with the weekend performances for the previous two releases: The first film, Harry Potter and the Sorcerer's Stone, grossed $90.3 million, and the second film, Harry Potter and the Chamber Of Secrets, grossed $88.4 million.

Let's get down to some raw, ahead-of-the-curve movie business analysis here. Although good figures are hard to come by, the latest Potter project probably cost around $180 million to make and sell. For each of the previous two films, that figure is between $150 million and $165 million, according to some sources. Bottom line is Azkaban, as would be expected, is the most expensive of the three celluloiders. If we look at the opening numbers for all three films, we see there is a bit of resistance hovering around the $90 million level. Furthermore, the first feature in the franchise grossed approximately $317 million; the second, $262 million. What that tells me is that Time Warner better hold the budget in check for the next four films, because Potter looks to be getting riskier with each new bet (in comparison to the ever-increasing grosses of the Rings films).

Harry could be a phenomenon that has already formed a plateau (at least in terms of theatrical exhibition; the books are another matter). I doubt Azkaban will take in much more money than Chamber of Secrets did for its entire domestic run, although it is too early to tell, since we don't have the second weekend to identify a definitive trend (my guess at this time is it might take in less, actually).

In fairness, though, there's a lot of strong competition out there with the second Shrek, which has already grossed more than its predecessor. I have a feeling, though, that Sony (NYSE:SNE) and Marvel Enterprises' (NYSE:MVL) sequel to 2002's Spider-Man will take some of the thrust out of Potter's broom when it captures moviegoers in its web of velocity-rich entertainment. And, as a Disney (NYSE:DIS) shareholder, I hope the upcoming tentpole flick The Village by M. Night Shyamalan steals thunder from both of those pictures.

Harry and the gang will still do well. Come fall, the DVD will sell plenty of copies at Best Buy (NYSE:BBY), and it'll be rented out by the magic-crazed moviegoers at Blockbuster (NYSE:BBI) and Netflix (NASDAQ:NFLX). My big thesis here is that the underlying economic model for the franchise should be evaluated carefully at this juncture, with the preservation of past profits being the paramount goal of the exercise.

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Fool contributor Steven Mallas owns shares of Disney.