The Flash 's Jesse L. Martin Joins HLN's How It Really Happened

CW Upfront Presentation, New York, America - 19 May 2016
CW Upfront Presentation, New York, America - 19 May 2016

Stephen Lovekin/Variety/REX/Shutterstock

Jesse L. Martin is adding another title to his resume: Host.

On Sunday, The Flash star will launch HLN's How It Really Happened with Jesse. L Martin, in which he delves into notorious crimes, mysteries trials, and tragedies.

"My agents, managers came to me and said, 'Here's an interesting project,'" Martin, 53, tells PEOPLE. "And I never thought of myself as a host, really, of anything. I rather enjoy being able to hide myself in a character. But this was such a cool project. It became a great, great gig for me."

Martin, who previously starred on Law & Order for nine seasons, just wrapped up an eight-year run on The Flash where he played detective Joe West. He's also a four-time Tony Award winner for his stage work. While his latest project is a departure from his long list of acting credits, he was drawn to the content.

"I'm fascinated by is mystery," he says. "Seeing it from the angle that I'm seeing it, as the host, is the most fascinating thing to me. It's amazing to be part of something where you're literally on the pulse of what's actually happening. These mysteries aren't solved, so they're continuously being investigated. So even as we air, the story's changing. That's really fascinating to me."

jesse-martin-2.jpg
jesse-martin-2.jpg

Shane Harvey/The CW

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Martin says he knew from a young age he wanted to be a performer, but he has also long been passionate about design.

"Since I was 11, I remember distinctly saying to myself, 'I want to be an actor,' but just before that I wanted to be an architect, which is where I am now," he explains. "I'm literally building my own house. It's the first house I ever designed and I'm really enjoying it."

Martins describes his aesthetic as "old world with all the modern conveniences — but by old world, I mean old, old world, almost tribal. But with Wi-Fi."

He's nearly 70% done with the home and says he can't wait to finish the project.

"I want the place to be healthy, I want it to breathe, I want it to be a place I go to and really, really recharge in every single way."

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How It Really Happened with Jesse L. Martin launches Sunday at 9 p.m. ET on HLN.