Looking back now, King Charles reflects on that period with a sense of quiet resolve. Despite the ridicule, he chose not to retreat from his views or soften his message to make it more palatable.

“I just felt this was the course I’d set which I should stick to,” he says in the documentary. “I wasn’t going to be diverted, I’m afraid.”

The film makes clear that his commitment to environmental causes never wavered, even when public opinion had not yet caught up with ideas that are now widely accepted.

A lifelong concern for the planet

The documentary also shows Charles speaking candidly about his worries for the future of the Earth. Asked whether he feels anxious about the state of the planet, he answers without hesitation.

“Of course. That’s been my main motivation for a long, long time, and you can see what’s happening,” he says.

He goes on to explain that the concept he refers to as Harmony, living in balance with nature, remains central to his thinking. “I’ve said that for the last 40 years,” he adds, acknowledging that while his influence may be limited, his sense of responsibility has never faded.