Jared Leto has kind of a reputation in Hollywood of being... well... challenging. Mostly because he absolutely loses himself in his characters. Jared is a method actor, through and through and it's probably why his performances have been heralded the way they have.

Given that he's played some rather complicated and disturbing characters, some of his onset behavior has gotten him into trouble. While many of his co-stars have said both positive and negative things about his style of acting, his refusal to break character while making a movie has gotten him into trouble in the press. Especially when he sent 'gifts' to his Suicide Squad co-stars.

One of Jared's most underrated roles was his deep-dive into the mind and body of an addict in Darren Aronofsky's 2000s film Requiem For A Dream. Given that Jared once shoved a casting director during an audition to stay in character, one can only imagine what he would've been like while actually making a movie about someone who has been completely taken over by drugs. According to Jared's Requiem For A Dream co-star, Jennifer Connelly, he could be quite "volatile". But that's not the entire story...

Jared Leto Went Full Method Actor On Requiem For A Dream

During an oral history of Requiem For A Dream by Vulture in honor of the film's 20th anniversary, the cast and director Darren Aronofsky went into detail about the way Jared worked on set.

"Jared definitely has a very method technique, and he really wanted to dive into the world of addicts and stuff," Darren claimed.

According to Jared Leto himself, he did everything he could in order to add more authenticity to the role. "It’s a film that demanded that," he said. "So I spent time with a group of people in the East Village, many of whom are no longer alive — they lost their battles to addiction. They were very supportive and helpful and generous with their time and their experiences and there were nights that I spent basically homeless."

His co-stars Jennifer Connelly and Marlon Wayans did similar things. They spend a lot of time with addicts talking about heroin addictions and really trying to understand a voice that is so often dismissed by society. It was heavy work. But it was a heavy film, and they needed to do it justice. But while all of them were mentally and emotionally invested in their characters, Jared became physically invested.

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While Jared claimed that no one forced him to lose weight for any movie he's ever done he did end up dropping a ton of weight, similar to what he did for his Academy Award-winning movie, Dallas Buyers Club.

"It was my idea [to lose weight], and I thought that given the circumstances, given my own personal experiences around addiction and addicts, it was appropriate, physically, that he’d be in that place. I also thought that if I lost a lot of weight and was restricting my food intake, that would put me in a place of constant craving. I thought that was a good place to be," Jared explained.

While Jennifer didn't go full method actor for her role as Marion Silver, she did keep Jared's energy on the film in order to give the project more weight. Marlon Wayans, on the other hand, would joke before and after takes. While he could remove himself emotionally, Jared and Jennifer couldn't and this could lead to some tension.

The Truth About Jared Leto And Jennifer Connelly's Working Relationship

"Our working relationship was good. It was at times slightly volatile — which I think was part of our characters and what they were going through at the time. It was sort of conveniently volatile during the volatile scenes, which was probably more of a reflection of our youth," Jennifer admitted in her interview with Vulture.

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Adding to this often "volatile" yet powerful dynamic were the differences in their training. Jared Leto came from a television background and learned how to really master a take by the second or third try. Jennifer, however, came from a film background and therefore took longer to really find the performance that suited the script. In film there's often more time to explore whereas, in television, actors are expected to nail their scenes as soon as possible due to production schedule demands.

"There’s a scene we shot, where Harry and Marion fight in Marion’s apartment, with a handheld camera," Matthew Libatique, the director of photography, said. "We shot it twice. Emotionally, Jared was really there between takes one and five, and Jennifer was better later. [Darren] comes to me one day. He’s like, 'I want to shoot that again. I’m going to shoot that scene again' I’m like, 'Are you kidding me? We don’t have the time to shoot that again.' And then I realized, he’s right. Because the actors needed a certain amount of time to be prepared for where they had to go."

Related: Why Jennifer Connelly Turned Down A Role In A Movie That Would've Made Her A Superstar

For Jennifer, the entire experience of working with Jared's incredible different style as well as the heavy material was challenging. As rewarding as she has claimed the experience was, she was also nursing a newborn baby on set. Meaning that she'd have to go from acting in an utterly devastating or high-intensity scene with Jared to coddling and loving a demanding baby.

"It was a very strange, split world, because the reality of my life was so different from the reality of Marion’s life at that time," Jennifer said. "It was the beginning of having to learn to surrender to the moment and not hold on to something. I had to learn to do all of my work ahead of time, and then surrender to the scene in the moments that I was there and we were filming, because I wasn’t really able to walk around inhabiting someone else’s world."

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