Long before he began his career as an actor and filmmaker, David Dastmalchian was a lifelong fan of comic books, including Batman: The Long Halloween. This summer, Dastmalchian will voice Julian Day, the supervillain Calendar Man, in DC Animation's two-part animated adaptation of The Long Halloween -- just before he takes on the live-action role of Polka Dot Man in The Suicide Squad. For Dastmalchian, both gigs are a dream come true. In the film, his animated character simultaneously advises and taunts the Dark Knight as Batman tracks a serial killer targeting victims on major holidays each month, just like he did in Jeph Loeb and Tim Sale's comic book story of the same name.

In an interview with CBR, Dastmalchian explained how both of his DC projects are part of a full circle moment for him on a personal level. He also shared the joys of taking on his first major vocal performance role and his insight on portraying Calendar Man.

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CBR: You ready to talk about our mutual friend Julian Day?

David Dastmalchian: I love this guy! It's interesting, because the first time I read The Long Halloween, I read it when I was in high school and I'll never forget [thinking] that character was so good and so cool. Wes Gleason does a lot of the casting for these films, as well as voice direction, and he told me that they were all really excited about me being Julian. It flipped my lid, I was so excited!

Speaking of Wes, he's a veteran in the industry and one of Warner Animation's best kept secrets. How was it working with him in the booth to develop your performance?

Dastmalchian: It was so cool! I basically walked into the booth and I'm standing there with a big, glass wall between me and the rest of the team, which is perfect. It's exactly how Julian exists in Arkham, just standing there looking out the glass. He's been imprisoned there for a long time and he'll probably be there for the rest of his life. I'm standing there with the director Chris [Palmer], Wes, [producer] Butch Lukic and our screenwriter Tim Sheridan was there on the first day of recording. They were all so excited and supportive of what I was doing. For me, it really helps to fully, physically embody the character when I'm doing my performance so, to be able to stand in that location, I actually felt like I was in a prison cell and I was just talking.

Wes had these great insights and it takes a special craft to be able to convey all the ideas and emotions and the magic of the text through just your voice when you don't have the opportunity to convey to an audience through your facial expressions and body. He would give me these wonderful, little insights to help with the inflection and pacing; it was all just like we were making music that day. It was super chilling and I enjoyed the fact that I seemed to get under their skin in a very good way. I hope my performance has the same effect on audiences who watch the film.

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Correct me if I'm wrong, but I think this is your biggest voiceover role to date. Some people find the booth intimidating or liberating. How did you find it exploring that space creatively?

Liberating, and you're absolutely 1000% correct. I haven't had an agent or manager for a few years now, but I was actually let go by a voiceover manager in 2014 because I couldn't book a job to save my life with voiceover auditions. I wanted, so badly, to be a part of the world of voice acting because I felt -- and my instincts were correct -- when I had the opportunity to finally do it, it was the most liberating and incredible, very much like black box theater, experience that you could ask for. The DC Universe movies that have been released by Warner Bros. over the years, all these incredible animated films, I'm such a fan of. I watched all these films and said what I wouldn't give to get a swing at one of these characters.

When Wes just emailed me out of the blue and said he and the rest of the team wanted me to become a part of this -- and for me personally, the fact that it was The Long Halloween -- my little geek heart melted. It was like every holiday on the calendar just at once for me. My wife was crying because she was just so happy for me when I got that email.

ABRA KADABRA The Flash

You've gotten to walk multiple superhero worlds, including the Marvel Cinematic Universe, the DC Extended Universe in The Suicide Squad and the Arrowverse as Abra Kadabra. How is it using these established superhero spaces as a creative canvas?

Dastmalchian: It's bonkers. It's like getting to live in the comic book dreams of my entire life everyday as living for a job and getting to bring some of the most interesting, unique and wonderfully rich characters to life in collaboration with some of the most talented artists working in the field right now. It's really to quantify what a dream is this is and it has been for many years now. When you're talking about Batman: The Long Halloween, it is important to point out that the very first time I got to be a part of a film production was The Dark Knight, which was a movie hugely inspired by The Long Halloween. That's been acknowledged many times before and it's a known fact.

Standing on the streets of Chicago filming my little scenes for The Dark Knight, I was just five or six blocks away from the little comic book shop where I would buy my comic books in Chicago. And now I get to watch a DC Universe movie that I'm in and play Calendar Man in. This summer is a very full circle moment for me as a performer and as someone who has been collecting and loving comic books my whole life.

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When developing your performance as Calendar Man, was there a specific line that informed your performance or did you just draw from your prior knowledge of the story?

Dastmalchian: It was a combination of all of the above. I had all these opinions and thoughts about how to manifest Julian in a way that would be best servicing the script while captivating the audience's imaginations and utterly fucking with Batman in the best possible way. Because his brain operates in such a special and unique way, the holidays of the year, days of the year and minutes of the day, all that calculation, is the way his brain and spirit sees life and the world. So every holiday is building to these moments that are beginnings and endings, our births and deaths. That's why, in my opinion, murder was a part of the agenda when it came to the way Julian operated before he was captured.

Walking into the booth that day and seeing the art -- it was a completely collaborative effort and that booth was filled with the artists that were helping to craft this film -- getting to see the way they were going to craft the look of Julian in the film, which is very true to the way he looks in the comic, but it also has its own spin on it. He's imposing and got such a large figure that looks like he could squish a neck with just a squeeze. At the same time, he's got a delicate, soft, thoughtful voice, which Wes really helped me sculpt. I thought about my voice just slipping through the glass into Batman's ears and climbing into his brain and flipping the pages of the calendar in his mind and toying with him in a wonderfully sinister way.

Batman: The Long Halloween, Part One stars Jensen Ackles as Bruce Wayne/Batman, Naya Rivera as Catwoman/Selina Kyle, Josh Duhamel as Harvey Dent, Billy Burke as James Gordon, Titus Welliver as Carmine Falcone, David Dastmalchian as Calendar Man, Troy Baker as Joker, Amy Landecker as Barbara Gordon, Julie Nathanson as Gilda Dent, Jack Quaid as Alberto, Fred Tatasciore as Solomon Grundy and Alastair Duncan as Alfred, along with Frances Callier, Greg Chun, Gary Leroi Gray and Jim Pirri. The film is scheduled for release on June 22. Batman: The Long Halloween, Part Two arrives digitally on July 27 and on Blu-ray on Aug. 10.

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