Jeremy Clarkson decides to get a flock of sheep. He thinks It's a genius business plan: Instead every year mowing the 300 acres without cropping, the sheep will do, keeping everything nice and tidy and fertilizing the soil. Moreover, he can sell their babies for profit. But he doesn't count with the added complications these high-maintenance animals will bring.

Brian Cox looks at our attempts to answer one of the most profound questions we can ask – are we alone in the universe? With scientists sending space probes to the furthest reaches of our solar system and beyond, the scientific search for alien life has begun. Inspired by a childhood love of science fiction, Brian still hopes to hear from ET. In this film, he explains why this search deserves to be taken seriously, and he explores the chances of it happening.

Jeremy Clarkson decides to become a naturalist. 'In just 30 years, insect numbers have dropped by 25% and they're still falling. Without insects, all life on Earth ends. Everywhere where insects like to live is disappearing and I've decided to do something about that. My plan is to make my hedgerows, my valleys, my woods, and my streams more attractive to creepy crawlies. In essence, I am going to leave chunks of the farm completely alone. I'm going to put Mother Nature in the driving seat. It's a process called wilding.'

Brian takes a fresh look at the concept of gravity, revealing it to be far more than just the force that makes things fall to the ground.
In the last three years, we've made profound discoveries about the nature of gravity and the way it behaves, and how this relates to the origin of the universe and strange things like black holes. Our theory of gravity has become the attempt to understand the nature of space and time.

As Covid-19 puts Britain on lockdown, Jeremy Clarkson suddenly finds that his biggest worries aren’t all related to the upcoming lambing season. 'If you're involved in food production, you are key worker. We're gonna save the nation!... I've smoked a million cigarettes and I've had pneumonia. If I get it , there's not a lot of hope... Am I panic buying? I bought five tins of sardines the other day'.

Time i s a concept which is so familiar, and yet recent discoveries have revealed it to be far stranger than we could have possibly imagined. In the final programme in the series, Brian explores the enigma of time - a phenomenon we take for granted but which is one of the biggest mysteries in the universe. He recalls highlights from his TV series that touch upon this conundrum.