I don’t want to be a bummer, but I’m getting worried about Anchorman: The Legend Continues. Don’t misunderstand me: no matter what happens between now and December, I’m still going to go see it. I would probably plunk down $11.50 to watch Ron Burgundy mow his lawn for ninety minutes (somebody get to work on that). But the early press on the movie, especially the leaked casting info that is ostensibly intended to bolster our enthusiasm, is having the opposite effect on me.

Before going further, let me be clear that I’m not just some crusty, old Anchorman hater. I love the original – probably a little more than it deserves. I’ve seen it a over a dozen times and even paid $50 for a rare DVD of Wake Up, Ron Burgundy – an alternate cut of the film made up of deleted scenes and subplots – before realizing it was available for free on YouTube. I am prone to quoting the film; when I am arguing with my wife, I often bust out, “I’m the man who discovered the wheel and built the Eiffel Tower out of metal and brawn.” I even own and regularly wear a Sex Panther t-shirt.

I want the sequel to be great, but it’s just not going to be. For starters, there are the unreasonably high expectations. When Anchorman: The Legend of Ron Burgundy was released, nobody really knew if Will Ferrell was headed for comedy superstardom. We knew he’d be big – but not this big. He had been brilliant in a supporting role in Old School and pretty damn funny in a children’s Christmas movie, Elf, but the jury was still out in some ways. So now that we expect brilliance from Ferrell, will he be able to deliver?

But there’s another problem. Right after the movie was announced, producer/director Adam McKay told The Playlist it would be filled with bit parts for Ferrell’s famous friends:

“We’re talking about for ‘Anchorman 2′ creating a murderer’s row of the best day players ever. Like having every single one line or three line role, just be someone we just love.”

He wasn’t kidding. Since then, the cameos has piled up. Harrison Ford, Meryl Streep, John C. Reilly, Greg Kinnear, James Marsden, Jim Carrey. Some of these are confirmed, others are just speculative. We can probably also expect a return for Jack Black, still smarting from that burrito to the face. And, of course, nobody will be surprised if Ben Stiller, Luke Wilson, and Tim Robbins show up again as Burgundy’s rival broadcasters.

In fact, that scene in  which the rival news teams engaged in a bloody clash – let’s call it Gangs of San Diego – gets to the heart of the problem. It was reasonable enough when Burgundy’s gang prepared to face down their chief rivals, led by Vince Vaughn in what would probably be called an “extended cameo.” At least his character had been established earlier in the movie. But then here comes Wilson, Robbins, and Stiller, who exist apparently only to make the viewer say, “Hey, there’s Luke Wilson, Tim Robbins, and Ben Stiller!”

Suspension of disbelief is crucial, even in a movie as silly as Anchorman. This is why the best cameos in film comedies usually occur when an actor is playing himself. Think of Bill Murray in Zombieland, Neil Patrick Harris in Harold and Kumar Go to White Castle, or even Marshall McLuhan in Annie Hall. These cameos keep us in the diegetic world because the characters react to them the same way we would. Just like Woody Harrelson in Zombieland, my reaction upon meeting Bill Murray in person would probably be, “BILL FUCKING MURRAY!”

On the flip side, I never laughed much at Tom Cruise in Tropic Thunder. His cameo as an enraged movie producer was drenched in novelty. At best, it was a subversion of our pre-conceived notions of the actor, but it still required us to simultaneously perceive him as an actor and a character. That’s tough on an audience.

Then, there are the lazier comedy cameos, like Will Ferrell himself in Wedding Crashers and Starsky and Hutch. Or Vince Vaughn in Zoolander. These bit parts have the same alienating effect as the cameos in Anchorman. We know that these guys – dubbed by the lazy media as the “Frat Pack” – like to work together, so it’s supposed to be fun when we see them pop up in each other’s movies, even if it’s only for a scene. But there is a big difference between these actors and, their namesake, the Rat Pack. Sinatra, Dean Martin, and company made tons of movies that relied on a similar principle – that we will enjoy watching some fun guys hanging out together on camera. But we loved the Rat Pack for their cool; we love the Frat Pack when they’re funny. And if the cameos in Anchorman: The Legend Continue don’t produce the funny, we might love them all a little less.

There is a right way to do this. If Ferrell and McKay are looking for some inspiration, they would be wise to look to the younger generation. Although the group hasn’t been given a name yet, actors Seth Rogen, Jonah Hill, Danny McBride, and Jason Segel have a way of popping up in each other’s films. So far, suspension of disbelief has not been a problem, because rarely are their roles reduced to cameos. They understand that character has to come first.

As proof of their mastery of the delicate art of the comedy cameo, consider their upcoming apocalyptic comedy, The End of the World, in which each of them – as well as James Franco, Craig Robinson, and Jay Baruchel – star as themselves. When they play and make fun of themselves, they create one universe of characters that we can engage with. And they still get to pal around on set. Movies like Anchorman: The Legend Continues want us to relate to the film both as a work of fiction and a documentary about a bunch of comic stars. And that’s just not conducive to good comedy.