It’s been eight months since Michael C. Hall was last seen on Showtime, and he wasn’t doing much good for the world. Or, rather, Dexter Morgan, the fictional serial killer he played for eight seasons on Dexter, wasn’t, having secluded himself as a lumberjack after butchering countless people and ruining the lives of others. Tonight, though, Hall is back on the network as himself and with an admirable, world-changing purpose.

In the latest installment of Showtime’s documentary series Years of Living Dangerously, Hall heads to Bangladesh to see firsthand just how serious the issue of climate change in that foreign, unfamiliar country. Rising sea levels are getting to the dangerous point of forcing upwards of 150 million people to flee to safer parts of the world, ratcheting up global migration to unmanageable degrees and also potentially causing devastating floods and widespread diseases.

With Hall as a wide-eyed guide, viewers will get a personalized look at the strong-willed Bangladeshi people at the heart of the matter, continuing Years of Living Dangerously’s overall mission of channeling crucial world issues through celebrity correspondents like Ian Somerhalder (The Vampire Diaries), Arnold Schwarzenegger, Matt Damon, Olivia Munn, and Harrison Ford.

While promoting his knockout indie thriller/neo-noir flick Cold in July two weeks back, Hall reflected on his journey to Bangladesh and the impact it had on him.

Like a lot of people, I recognize and appreciate that it’s as fundamental and pressing an issue as we face. I’m frustrated, as an individual, with a sense of powerlessness and an inability to do anything about it. So when I was invited to take part in this, I jumped at it. It’s a story worth telling; it’s a story that people need to hear. It was actually right on the heels of Cold in July. Shortly after we finished shooting that, I went to Bangladesh and did this. It was an eye-opener. I hope it’s something that people will watch not only on Showtime, but elsewhere, too, because it gives a comprehensive sense of the issue’s depth and breadth.

Initially, they told me about Bangladesh and another story in North Carolina, which is where I’m from. I decided that the idea of going to the other side of the planet was cooler to me, and more interesting. Once I got there, everything was very eye-opening. The temperature, in particular, really took me aback. It was so humid, and there were people absolutely everywhere. The density of the population—especially in the capital city of Dhaka, where we started—was pretty phenomenal.

We pretty much immediately started shooting. I took a quick nap and a shower, and then we went out by the train tracks. I initially talked to this migration specialist, and then from there it was really non-stop. We were with this expert crew of non-embedded war correspondents and experienced news crews and cameramen. They’re used to maneuvering through situations and locations like that, so I was in very good hands. Playing the news correspondent’s role was an interesting one—there was a steep learning curve.

I think, more than anything, I was just amazed by the spirit and the reserve of the Bangladeshi people. They’re really amazing people. At first, it was really intimidating, though. I was required to embrace the mystery of it. I didn’t know what I was getting into, and I think that’s what they’re going for with the Years of Living Dangerously series, in terms of these curious non-expert correspondents. Through them, we, as an audience, get to know the in’s and out’s of this specific story and the greater issue. It was a leap of faith and a total adventure into the unknown. That made it scary but also fun. That was a big part of the appeal.

I now certainly have a much more informed understanding of the issue and I’m more inclined to follow it and see how things are developing. In this country, I feel like maybe any sort of huge systematic change will have to come from a private sector or organization. It is a money-drive culture; if somebody creates a really cost-effective and moneymaking technology that allows us to move forward positively on climate change, that’s what it’s going to take for us to really make a difference.

Michael C. Hall's two Years of Living Dangerously episodes, "A Dangerous Future" and "Moving a Mountain," air tonight and next Monday, 6/9, at 8 p.m. EST, respectively.

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