Now we can see how Batman began even before "Batman Begins."

Christian Bale may have officially exited the Batcave for good with his final performance as Bruce Wayne in "The Dark Knight Rises" (2012), but he has left behind a formidable legacy as the actor whom many feel made for the best-ever Batman. Bale brought a strong sense of physicality and authority to the role, as well as a much-debated distinctive vocal register ... a trait he conjured even before he was cast in the part.

Bale's original audition tape from "Batman Begins" (2005) reveals the actor in full Caped Crusader costume (the one Val Kilmer wore in 1995's "Batman Forever," for the record) and performing a key scene with Rachel Dawes (read by none other than future "Man of Steel" star Amy Adams). Kilmer's more stylized costume is a bit incongruous with what would be the grittier, more realistic tone of "Begins," but Bale's Dark Knight persona shines through the wardrobe as he delivers soon to be iconic lines like, "It's not who I am underneath but what I do that defines me" — almost exactly the way he would in the final film.

See Christian Bale's Batman Audition (With Amy Adams!):



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The video also reveals that Bale was experimenting with his Batman voice from the get-go, bringing a sense of mystery and danger to his words with a deep, commanding tone. Director Christopher Nolan explains that while Bale projected "massive energy through this costume," it's the voice that really made the Bat-man.

"Christian's voice was a big part of the impression he made in the test," says Nolan in the video. "He decided that Batman needed to have a different voice than Bruce Wayne; he needed to put on a voice that supported the visual appearance of the character."

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To be fair, Christian Bale isn't the first actor to make Bruce Wayne and Batman vocally distinctive from each other. Michael Keaton had a low-register, almost sensual tone for his Caped Crusader (his delivery of "Eat floor; high fiber" was downright sexy in 1992's "Batman Returns") and Val Kilmer's Batman had a deeper voice than his Bruce Wayne in "Batman Forever" (whereas George Clooney just sounded like George Clooney in 1997's "Batman & Robin," but let's not get into that). However, Bale's Bat-voice ended up being the subject of some debate ... especially by his second turn as Batman in "The Dark Knight" (2008), in which the deep tones of "Batman Begins" were made even raspier (and sometimes extremely hard to understand) through post production tinkering.

Actually, the Batman of "Batman Begins" was designed to sound different from the start. The production notes from the film reveal that Batman's cowl is equipped with mics and speakers (see image above) that allow him to both monitor police and emergency services radio frequencies and enhance his speaking voice.

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"High-gain stereo microphones are concealed in the ears, allowing Batman to eavesdrop on distant conversations," the notes describe. The mics can also amplify Batman's voice and broadcast it through a discreet speaker in the suit, giving his voice that distinctively gruff, disembodied sound.

While the original script included a scene that went over these Bat-details, mentions of Batman's embedded vocal distorter wound up being cut from the final film. (Still, the Batsuit's tiny speakers remained visible upon close inspection.)

Bale's audition video also makes for a fun scenario for fans, as a near-future Batman performs a scene with a later-future Lois Lane. Amy Adam was reportedly reading the part as a favor to the casting director of "Batman Begins" (we assume specifically John Papsidera, who was the casting director on the Adams-starring "Drop Dead Gorgeous") and was never a candidate for Rachel Dawes. But she'll be acting opposite a new Batman, Ben Affleck, in the upcoming "Man of Steel" sequel.

The Christian Bale audition video and many more never-before-seen extras can be found on "The Dark Knight Trilogy: Ultimate Collector's Edition" Blu-ray and DVD box set, which will be released on Tuesday.

Also Watch 'The Dark Knight Rises' Blu-ray Trailer:

