Michael Keaton, while an unorthodox choice for an action movie star, remains iconic as Bruce Wayne in Tim Burton's 1989 Batman and 1992 Batman Returns. Burton's takes on the Caped Crusader were theatrical and critical successes, earning both tons of money and rave reviews. Aside from Jack Nicholson's Joker and Danny DeVito's Penguin, much of the success of Burton's films rests on Keaton's dynamic performance as Batman.

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The evolution of Tim Burton's Batman from script to screen is a tale predicated on thinking outside the box. From the design of the Batsuit to Keaton's action choices, this iteration of Bruce Wayne brought Batman's darker side to cinemas. Here are 10 facts about Michael Keaton's Batman you may not know.

Keaton Was A Typecast Actor At The Time

Michael Keaton's first big breakout role is Jack Butler in 1983's Mr. Mom, a wholesome comedy about a stay-at-home dad taking care of his three young children after his wife returns to work. Due to the success of the movie, Keaton struggled to get dramatic roles.

Throughout the rest of the 80s, Keaton acted in many comedies, culminating in Tim Burton's 1988 classic Beetlejuice. Keaton's attempts to break away from being typecast as a comedic actor were unsuccessful.

Multiple A-List Actors Were Considered For The Role Before Keaton

After Tim Burton reached a deal with Warner Bros. to direct a new installment of the Batman franchise, he was pressured to cast a well-known action star in the title role. Burton approached Pierce Brosnan, but the future 007 had no interest in playing a comic book character.

Other actors on the short-list to become Batman include Mel Gibson, Kevin Costner, Harrison Ford, Dennis Quaid, and Tom Selleck. Charlie Sheen, Bill Murray, and Willem Dafoe were even considered.

Keaton's Performance In The Movie Clean And Sober Helped Him Land The Role

Batman producer Jon Peters suggested Michael Keaton for the role. Keaton finally broke out of his comedy shtick and landed the lead in 1988's Clean and Sober. In the film, Keaton plays a cocaine-addicted real estate agent in Philadelphia.

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Peters believed Keaton could pull Batman off due to the dark, tense performance he gives in Clean and Sober. After working with Keaton in Beetlejuice, director Tim Burton agreed.

Warner Bros. Received Thousands Of Protest Letters Over The Casting

When Warner Bros. announced Michael Keaton would play Batman, the backlash was immense. The production company received over 50,000 letters in the mail from fans who felt Keaton was the wrong choice.

Most of the criticism came from comic book fans who thought Keaton would make Batman too campy and comical. They feared a return to the 60s era Batman starring Adam West.

Batman Co-Creator Bob Kane Also Questioned The Choice

As a result of the controversy surrounding the choice to have Tim Burton direct and Michael Keaton star in Batman, producers asked Batman's co-creator Bob Kane to sign on as a consultant.

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Kane agreed, but he also questioned the decision to cast Michael Keaton as Batman. As Kane learned more about Burton's vision for the film, his criticism subsided.

Bob Ringwood Designed Keaton's Batsuit In 1989's Batman

Bob Ringwood served as the costume designer for David Lynch's Dune and Steven Speilberg's Empire of the Sun before signing on to create Michael Keaton's Batsuit. Ringwood was tasked with making Keaton -- who is of average build -- look like a larger-than-life superhero.

Ringwood chose an all-black suit for Batman. With $250,000, Ringwood made 28 latex Batsuits, 25 of which donned capes. Ringwood also made six headpieces for Keaton. Ringwood studied hundreds of comic books for inspiration.

Hoping to make some extra dough via product placement, producer Jon Peters suggested including the Nike logo on the Batsuit. Tim Burton vetoed this idea, but he agreed to let Nike design Batman's boots.

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Inspired by Nike Air Trainers -- which were popular at the time -- the boots stick out in a film inspired by stylings from the 40s. Fortunately, the boots are not featured in too many scenes.

The Suit Was Upgraded For 1992's Batman Returns

Bob Ringwood returned to handle the costume design in 1992's Batman Returns. Michael Keaton also returned in the title role. Ringwood updated Keaton's Batsuit, opting to use thin foam rubber instead of latex.

The new Batsuit not only gave Keaton more breathing room: it also granted him greater mobility. The Batsuit in the sequel lacks the athletic sculpting of its predecessor; it also incorporates a more defined logo.

Keaton Is The First Batman To Change His Voice While Costumed

Michael Keaton felt it was necessary to make his voice lower when in costume as Batman. Differentiating the vocal tones between Batman and Bruce Wayne seemed logical to Keaton, who thought it would be too obvious that Bruce Wayne and Batman are one and the same if he didn't alter his voice.

Keaton's decision influenced Christian Bale's interpretation of the character in the Christopher Nolan movies.

Keaton's Batman Is Inspired By Darker Comic Interpretations Of The Character

Tim Burton's movies take a much darker turn than previous adaptations of Batman comics. Sam Hamm's screenplay for Batman was inspired by brooding characterizations of Batman in Alan Moore's The Killing Joke and Frank Miller's The Dark Knight Returns.

While Michael Keaton refused to reprise his role when Joel Schumaker took over the franchise after Burton, but his stints as Batman paved the way for Christopher Nolan's darkly realistic look into the life of the Caped Crusader.

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