'Iron Man' Recasting Makes Us Wonder: Does Swapping Actors Ever Work?

We look at 'Dark Knight,' 'Terminator 3' and other recent switcheroos to see how Don Cheadle might fare.

Given how vocal and enthusiastic Terrence Howard has been about playing War Machine in "Iron Man 2," it was a shock to read that the actor has left the project over rumored financial issues. Will newly hired Don Cheadle live up to the role? Will fans worry about the continuity? Will he stick out like a sore thumb?

History, unfortunately, isn't on his side. We took a look at five recent high-profile cast changes in comic book or fantasy movies to gauge whether the new actor was successful in replacing an already-established actor. Then, just for fun, we took a look at some of the current castmembers of big-budget films who should be replaced — paying special attention to movies officially in the works (so no "Fantastic Four" and no reboots, like "Daredevil").

Read all our thoughts below, and then let us know what you think in the comments section.

(What's the early verdict on Cheadle and Howard? Find out on the Splash Page blog.)

"The Dark Knight"

Who's In/Out?: Maggie Gyllenhaal replaces Katie Holmes in the role of Assistant District Attorney Rachel Dawes.

The Fans Say: Given its surpassing excellence, "Batman Begins" somewhat underperformed at the box office, barely squeaking by $200 million domestic. At the time, some pointed to Holmes as a possible reason, as her antics with new husband Tom Cruise were viewed as a tabloid distraction (see also: the underperformance of "The War of the Worlds" that same summer). For her part, Holmes says she voluntarily left the project to pursue other movies. Whatever the reason for her ouster, however, most agree that Holmes was the weak link in the first story. In the end, though, that was essentially the same thing they said about Maggie Gyllenhaal in film two. Gyllenhaal did prove to be better suited to the darker tone of the material and was an enthusiastic supporter of the film in the press. It's hard to argue with any choice that even tangentially pushes a movie into becoming the second-highest earner of all time.

The Verdict: Replacing Holmes was the right move.

"Mummy 3: Tomb of the Dragon Emperor"

Who's In/Out?: Mario Bello replaces Rachel Weisz in the role of Evelyn Carnahan O'Connell.

The Fans Say: Meh.

The Verdict: Meh.

"Batman Forever"

Who's In/Out?: Val Kilmer replaces Michael Keaton in the role of Bruce Wayne/ Batman.

The Fans Say: It's tough to look at the Joel Schumacher "Batman" films now as anything other than complete travesties — celluloid failures that set the franchise back nearly a decade. But with its campy and more juvenile tone, "Batman Forever" was a huge hit at the box office, totaling more receipts than any other film in 1995, save the original "Toy Story." In retrospect, of course, the films are thought of with the derision they deserve, even if little of that derision is laid at Kilmer's feet (the vision is thought to be entirely Schumacher's). Keaton, of course, was the first to warn fans — by deciding not to do the third movie — of the direction the series would ultimately take. It should have been a sign.

The Verdict: They should have listened to (and kept) Keaton.

"Terminator 3: Rise of the Machines"

Who's In/Out?: Nick Stahl replaces Eddie Furlong in the role of John Connor.

The Fans Say: "Terminator 3" should never have been made. Period. But, considering they had no say in the matter, fans reacted positively to Stahl, who reportedly replaced Furlong as humanity's great savior because the latter had drug issues at the time of filming. The consensus seems to be that Stahl acquitted himself admirably in the role, though it's also worth nothing that his performance doesn't have the same cultural resonance as Furlong's — probably because the movie itself hasn't seeped into the consciousness the way the earlier film has.

The Verdict: Stahl did well but was betrayed by an overall lackluster installment.

"Harry Potter and the Prisoner of Azkaban"

Who's In/Out?: Michael Gambon replaces Richard Harris in the role of Professor Albus Dumbledore.

The Fans Say: Producers had little choice in the matter, considering Harris' passing sometime after the second film in the series. Still, the fan community agrees that in choosing Gambon as a replacement, the Potter brain trust committed its biggest casting misstep. Gambon, who has admitted to having not read the novels, changes Dumbledore from a wise, kindly soul into a man seemingly possessed by rage and anger. He yells a lot. Fans, meanwhile, yell at the screen for wrongly portraying their favorite headmaster.

The Verdict: Considering the wealth of other potential options, Gambon was a disastrous misstep for a franchise that prides itself on casting.

Those Who Should Be Replaced

Kirsten Dunst as Mary-Jane Watson in "Spider-Man" sequels

The Babe Ruth of failure to Holmes' Lou Gehrig, Dunst has faltered through three "Spider-Man" movies as the web-slinger's oft-imperiled, on-again/ off-again love interest. Dunst told MTV News that she's in for the sequels. Let's hope she can find an emotional range beyond "wet blanket." And, great Mighty Thor, whose idea was it for her to sing?

Brandon Routh and Kate Bosworth as Clark Kent and Lois Lane in "Superman"

We know that Warner Bros. and DC are rebooting their "Superman" franchise. What we don't know is whether they'll do so while bringing back the stars of "Superman Returns." They both need to go up, up ... and away.

Halle Berry as Storm in "X-Men"

It seems unlikely that the "X-Men" story will continue with a fourth adventure in the Bryan Singer narrative, given how the characters seem to be going the prequel route with next year's "Wolverine" and the planned "Magneto." It's equally unlikely, it seems, that Berry would want to return even if there were a role somewhere for Storm. It's imperative, however, if both the above assumptions prove false, that Berry not actually return — her wooden line readings ("You know what happens to a toad when it gets hit by lightning?") are a laughable low point for the series.

Check out everything we've got on "Iron Man."

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