"Amsterdam" is the third collaboration between director David O. Russell and Christian Bale, and even though their latest 1930s-set period piece didn't exactly light the box office on fire, both artists still have every intention of working together again. After winning an Oscar for his role in Russell's "The Fighter," Bale played a con man in "American Hustle." Shortly after that, the idea for "Amsterdam" slowly started to come together, allowing Bale to carefully craft the character of Burt Berendsen, an injured World War I veteran who vows to help other returning veterans get a leg up in New York City during the Great Depression.

A dedicated actor like Bale takes the art of imitation to an entirely new level when he's developing a character, creating every aspect of his next role from the ground up. The quirks and eccentricities that Bale incorporated into Burt became so innate that it became difficult to separate the character from the performer. Although Bale wasn't a credited writer on "Amsterdam," he was instrumental to the entire story from the start, telling Indiewire "It was wonderful to be that baked into the whole process. By the time we came to actually start filming, Burt was sort of in my bones."

Becoming that immersed can sometimes give off an air of pretentiousness, and it can also lead to some odd behavior that might be misconstrued if it was ever called out in public. When Bale was still figuring things out, he wound up mimicking a perfect stranger on the street one day to help find Burt's unique physicality. Hilariously, the man Bale was eyeing had no clue that he was being followed by one of the most recognizable stars in the world.

'He's A Big Influence'

Knowing the level of dedication to the craft from his on-screen performances and seeing his personality come through in various interviews and awards speeches over the years, it seems perfectly reasonable that Bale would commit such a random act of weirdness. In a recent Entertainment Weekly interview, Bale fessed up to finding inspiration from an unlikely place:

"I remember one time talking on the phone to David [O. Russell] and I saw this amazingly interesting guy walking down the street. I just became a weirdo stalker following him and studying him. So he's a big influence, whoever he is out there. I don't know his name. He'll never know, either."

Admittedly, it would be more of a compliment to this random stranger if Burt Berendsen became one of Bale's most iconic roles. Instead, the performance will most likely go down as an example of leaning a little too far into Bale's unconventional instincts. Glass-eyed TV detective Columbo (Peter Falk) also became a small piece of Burt's character puzzle, which makes perfect sense actually.

Even when he goes a little left-of-center, Bale still remains a consummate professional who really seems like he was meant to be an actor. Researching and pretending to be someone else can be a very serious undertaking and a process that stays with you for a long time. For the trick to truly work, a performer has to fully dedicate themselves to really becoming someone else. Bale is constantly searching, telling EW: "I don't begin to understand people ever. That's why I think I love doing what I do, because I'm endlessly confused but delighted by them."

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