David Letterman fronts the first episode in a new series of the US climate change documentary, produced by Hollywood heavyweights James Cameron and Arnold Schwarzenegger. Tonight, the focus is on solar energy and it’s a tale of two very different worlds.

Letterman is in India, where 300 million people have no electricity, and those who do rely heavily on coal. The government has embarked on an ambitious plan to get India powered by solar in just six years.

In the US, however, actress Cecily Strong reports on alleged political corruption and wrongdoing, which is stopping solar energy even getting off the ground.

If we’re to have any hope of halting climate change, then this is essential viewing.