After living for nearly a hundred years on this planet, I now understand that the most important place on Earth is not on land, but at sea.”"Today, it is in such poor health I would find it hard not to lose hope were it not for the most remarkable discovery of all,

The naturalist has been on our screens for more than seven decades, presenting TV programmes including Planet Earth and Blue Planet.

Everyone's favourite nature narrator is entering into his 100th year and releasing a brand-new documentary. But this is not a gentle reflection on the past century: it's an impassioned call to arms.