Paul Dano had several near-sleepless nights while filming The Batman.

The There Will Be Blood actor stars as the Riddler in director Matt Reeves’ rain-soaked new Dark Knight film — and this take on the puzzle-loving rogue is a far cry from Jim Carey’s colorful and hammy version in Batman Forever. Inspired by the Zodiac killer, Reeves reimagined the Riddler as a serial killer who targets Gotham’s (likely corrupt) politicians and leaves taunting messages for Batman (Robert Pattinson) at his crime scenes. The role took Dano to a dark place.

“There’s a sequence with Peter Sarsgaard’s character [Gotham district attorney Gil Colson]. That was intense,” Dano tells EW. “There were some nights around that I probably didn’t sleep as well as I would’ve wanted to just because it was a little hard to come down from this character. It takes a lot of energy to get there. And so you almost have to sustain it once you’re there because going up and down is kind of hard.”

Paul Dano as Edward Nashton a.k.a. the Riddler in ‘The Batman.’.
Jonathan Olley/DC Comics/Warner Bros.

Another uncomfortable night was partially of Dano’s own making. Like Batman, the Riddler has his own homemade costume and mask in the movie; however, as Dano was preparing for the role, it occurred to him that his meticulous murderer should also cover himself in plastic wrap to avoid leaving any DNA evidence at his crime scenes. Reeves loved the idea, so they tried it out; however, things took a turn after an hour because of how hot Dano got under the mask.

“He took off the mask. He was beet red,” says Reeves, recalling that day on set. Dano adds: “My head was just throbbing with heat. I went home that night, after the first full day in that, and I almost couldn’t sleep because I was scared of what was happening to my head. It was like compressed from the sweat and the heat and the lack of oxygen. It was a crazy feeling.”

Nevertheless, Dano persisted with this plastic idea (Luckily, the costume department found a way to get more oxygen into the mask to make it slightly more comfortable). But this is likely the kind of commitment Reeves expected when he cast the Prisoners actor as the Riddler. According to the director, he started thinking about Dano for the part while he was writing the script, which was also the case with Pattinson.

“Paul is really a chameleon,” says the Cloverfield director. “He’s brilliant in so much. But I think you see him going through a very internal tortured experience in his characters. You can see him really in an active way, having this kind of psychological turmoil that I find is really compelling.”

Paul Dano.
Kevin Winter/Getty Images

Meanwhile, Dano had always wanted to do a superhero movie, but nothing had really piqued his interest until Reeves reached out about The Batman.

“[I was] waiting for the right one or ones, where you’re in collaboration with people and material that excites you. And this was definitely that,” says the actor, who was visiting his parents when Reeves sent him the script but couldn’t tell them. “I was totally surprised, frankly, that [the script] was so good. I felt immediately [on] page one, page two, you could tell that the director was seeing the film that they wrote. You could feel, even in the action scenes, the type of energy behind the fighting or the violence, it was just very fully conceived.”

Robert Pattinson and Paul Dano in ‘The Batman’.
Jonathan Olley/DC Comics/Warner Bros.

Dano got even more excited about the prospect of playing the Riddler when he hopped on the Bat-phone with Reeves after reading the script. “One thing Matt and I spoke about immediately was the two sides of trauma,” says the actor. “Bruce Wayne, as a child, experiences this trauma and the Batman is born of that. Sometimes we can take our scars or whatever you want to call it, and that can be fuel for a fire that drives one towards greatness at times. There’s another side of that coin, where those traumas, scars, and pains drive you in another direction. And I thought that was really powerful in the script. I thought that the sense of good and evil was not as black and white as it often is in a superhero film. And I thought those gray areas were really exciting.”

The actor adds: “What I felt was the opportunity that Matt was giving with a villain in this film was the more real, potentially the more terrifying.”

Compared to the villains in previous Batman movies, the Riddler functions somewhat differently in The Batman. He doesn’t have a movie-stealing presence like, say, Heath Ledger’s Joker in The Dark Knight, because Reeves didn’t want the rogue to take over the film. The focus had to remain on Batman. Nevertheless, the Riddler does present a unique threat to the Caped Crusader.

“The Riddler is omnipresent, but almost as a ghost,” says Reeves. “When I came up with the idea that the Riddler would be sending correspondence to Batman, [what] was captivating to me was if you’re a character whose mode is to work as a symbol, be anonymous, to come out of the shadows, nobody is supposed to know who you are; your power comes from the fact that you’re anonymous. Then suddenly someone starts to rob you of your anonymity, you start to lose a bit of your power and it starts to unsettle you.”

Reeves continues: “The flip side of that is that by withholding the Riddler, he had more power, he was more unsettling. He felt like a ghost throughout the whole movie, this kind of presence that you never knew where he would show up and how he was affecting things. And that that mystery would put Batman in a very vulnerable position because he didn’t understand from where and how and what the Riddler was acting.”

While the Zodiac killer was a major reference point for Reeves — especially for his look, which was inspired by drawings of the real killer — Dano didn’t think about his rogue in those terms. “I always felt instinctually that the Riddler is just so much more than that in terms of his intent and purpose, so I didn’t get too into the Zodiac Killer, frankly,” says Dano, who didn’t base his performance on a specific comic book either.

Even though the Love & Mercy actor had high hopes for the movie, he still can’t believe how much fun he had in his first foray into the world of superheroes. “It’s funny to be in something that has this much fan culture and fervor around it. And to my surprise, I’m really enjoying it,” says Dano. He especially loved shooting the moment when the GCPD and Batman surround the Riddler at a diner, which is the first shot of the trailer. “Seeing what Matt was doing, what the camera was doing, and Rob out the window…It just felt like, ‘F—, this is making a movie. Like capital M movie.'”

The Batman opens in theaters March 4.

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