[Spoiler warning: This article is about a major plot point in "Iron Man 3."]

Imagine if, in a Batman movie, the Joker wasn't really the Joker: How would fans react?
Would they love the twist? Would they hate the twist? Or would they react like Iron Man fans?

Oh, yes, Iron Man fans know all about twists.

In the just-released "Iron Man 3," Ben Kingsley, who is billed as our armored hero's arch nemesis the Mandarin, is revealed to be a down-on-his-luck actor hired to play the Mandarin by mad scientist Aldrich Killian (Guy Pierce).

The departure from comic lore was the brainchild of "Iron Man 3" writer-director Shane Black.

"It was nerve wracking," Marvel Studios president Kevin Feige told ComicBookMovie.com of the decision to greenlight the change.

If Tony Stark's keepers were worried, then Iron Man's followers were distressed.
Unless, that is, they were elated.

Jim Littler, editor in chief of ComicBookMovie.com, says he thinks the love-it/hate-it camps are about even in membership.

"The comic-book purists, the ones who know the comic books, they did not like the Mandarin twist mainly because that's Iron Man's biggest villain," Littler says. "...[But] overall people that aren't familiar with it, and even the purists will say it's well-executed, that it's a good movie."

Mandarin seemed to be a thorny issue for producers ever since it was announced he would be the key villain and he would be played by Kingsley, a Brit. Black insisted he wouldn't trade on stereotypes for the character.

(Disney and Marvel know the value of appeasing Chinese audiences. To get by censors, the name of the character was changed to "Man Daren," according to Reuters. To presumably broaden its appeal to local fans, four minutes were added to the film featuring Iron Man being cheered by Beijing students, Tony Stark being operated on by a Chinese doctor [Wang Xueqi], interacting with a new assistant [Chinese pinup Fan Bingbing], and blatant product placement for a noted beverage maker, per The Hollywood Reporter.)

Certainly, the Mandarin bait-and-switch didn't seem to keep fans out of theaters. "Iron Man 3's" $174.1 million opening weekend was a new best for the Robert Downey Jr. franchise, and the second-biggest domestic start in Hollywood history. Internationally, it's closing in on $700 millions, including a record breaking run in China.

On the critical scale, "Iron Man 3" drew, on average, slightly better reviews than "Iron Man 2."

Writing for Movies.com, Jacob S. Hall praised Black's take on the Mandarin -- "an awful villain on paper, a 'yellow peril' Asian stereotype that may have been passable in the '60s but is wildly offensive today" -- and hailed the reinvention as "one of the best and smartest comic book villains since, well, ever."

Even in a taking-the-movie-to-task piece for slashfilm.com, David Chen allowed that the Mandarin twist brought him "a moment of geek joy."

"It's mildly exhilarating when a summer tentpole release can still surprise you," Chen wrote.

But just as no hero emerges from a comic-book movie entirely unscathed, no movie emerges from an encounter with die-hard comic-book fans entirely unscathed, either.

Shouted the apparently aggrieved fan-made GIF: "Ben Kingsley Is an Imposter!!!"

See Ben Kingsley and the cast of 'Iron Man 3' discussing the villainous Mandarin: