David Letterman already has plans to return to the small-screen after retiring from the Late Show.
The former late night host will travel to India for an episode of the National Geographic Channel's Emmy-Award winning documentary series, Years of Living Dangerously, to address the issue of climate change.
Variety reports Letterman's episode will focus on the country's efforts to increase its use of solar energy over the next decade. The project is the veteran host's first since retiring earlier in 2015.
Letterman is one of many celebrities who will appear on the National Geographic Channel series next season; others include Ty Burrell, James Cameron, Don Cheadle, Arnold Schwarzenegger and Olivia Munn, according to the Associated Press.