We love nature and all its glorious diversity. Some creatures we admire for their deadly beauty, others because they are cute, but for some it's hard to figure out exactly why we like them so much, perhaps it's a quirk. How do you decide nature's weirdest animal? Is it the sloth that hangs upside down and moves so slowly that moss grows in its fur? Is it a sea pen that sits rooted to the seabed in endless darkness and emitting its own glow? Could it be carnivorous snails that leave the ocean to digest dead creatures on the beach, finches that drink blood, or the tarantula that keeps a frog as it's pet. But with nature's endless variety, which is the weirdest? We can't decide. Can you?

Bladderwort utricularia is a pond-dweller that is among the fastest known, its traps snapping shut in less than a millisecond. As the seasons change, David demonstrates how plants operate on a different time scale to us; how they modify their lives according to the time of year. We discover insects’ hidden links with plants, both as pests and pollinators. UV-sensitive 3D cameras reveal the invisible alter-ego of plants and their flowers’ mesmerizing patterns; a parallel-dimension of strange colours and stunning patterns through which plants communicate with them. With the aid of visual effects, David steps among the swirling vortices of plant scent; communication signals with which plants are inextricably plugged in to the natural world. And using a tuning fork, he demonstrates how plants and insects can even communicate with music. As autumn envelopes the Gardens, fungi reveal themselves not as the enemies of plants but their vital allies. In Kew’s atmospheric Fungarium, David discovers a specimen that has the power of mind control and another that lives underground where it has grown to be so big it can be counted as the largest single organism on the planet. It is 6 times bigger than Kew Gardens itself.

The film documents the English heavy metal band Black Sabbath's final show of their farewell concert tour, The End Tour. The performance was held at the Genting Arena in Birmingham, England, hometown of the band's founding members: vocalist Ozzy Osbourne, guitarist Tony Iommi, bassist Geezer Butler, and drummer Bill Ward. Osbourne, Iommi, and Butler performed this final concert with session drummer Tommy Clufetos in place of Ward, as well as Adam Wakeman on keyboards and guitar.
The concert opens with a performance of the song 'Black Sabbath'. The film goes on to show the band performing 'Fairies Wear Boots', 'Under the Sun/Every Day Comes and Goes', 'Into the Void', 'Snowblind', 'War Pigs', 'Hand of Doom', 'Iron Man', and 'Children of the Grave'; at the end of the setlist, the band performs the song 'Paranoid' as an encore.
Interspersed with the final concert are interviews with Osbourne, Iommi, and Butler, in which they talk about their careers and past drug addictions. Additionally, Iommi's 2012 lymphoma diagnosis, which impacted the band's 2012–14 reunion tour and the recording of their 2013 album 13, is discussed. The film also features footage of 'The Angelic Sessions'—the band's final studio recordings, which took place in the days following the final show. Of these recordings, the film shows Osbourne, Iommi, and Butler performing 'The Wizard', 'Wicked World', and 'Changes'.

Earth’s oceans help make our planet different from every other planet in the solar system. As far as we know, no other place is the right temp for liquid water, the most essential ingredient for life to exist. The oceans are Earth’s primary stabilizing force, and their immense power helps to shape the appearance and behavior of the entire planet and everything living on it. And they are also the planet's great unknown - their deepest points have been visited less than the surface of the moon.

It was the defining moment of the 20th Century - the scientific, technological, military, and political gamble of the world's first atomic attack. This drama-documentary attempts to do what no other film has done before - to show what it is like to live through a nuclear explosion, millisecond by millisecond. Set in the three weeks from the first test explosion in New Mexico to the eventual dropping of the bomb, the action takes viewers into the room where the crucial political decisions are made; on board the Enola Gay on her fateful voyage; inside the bomb as it explodes; and on the streets of Hiroshima when disaster strikes. Parallel storylines interweave, unfolding the action from both US and Japanese perspectives, and revealing the tensions and conflicts in the actions and minds of people who were making history. Special effects recreate the reality of the mission - even going inside the workings of the bomb - and archive film replays the horrific aftermath.

The third episode is devoted to the ways in which plants reproduce. Pollen and a stigma are the two components needed for fertilisation. Most plants carry both these within their flowers and rely on animals to transport the pollen from one to the stigma of another. To do this, they attract their couriers with colour, scent and nectar. It isn't just birds that help pollination: some mammals and reptiles also do so. However, it is mostly insects that are recruited to carry out the task. To ensure that pollen is not wasted by being delivered to the wrong flower, some species of plant have developed exclusive relationships with their visitors, and the gentian and its attendant carpenter bees is one example. Since pollen can be expensive to produce in terms of calories, some plants, such as orchids, ration it by means of pollinia and a strategically placed landing platform. Other orchids offer no reward for pollination, but instead mislead their guests by mimicking their markings and aroma, thus enticing males to 'mate' with them (Pseudocopulation). The most extreme fertilisation method is one of imprisonment, and one plant that uses it is the dead horse arum. It is often found near gull colonies, and mimics the appearance and smell of rotting flesh. Blow-flies are attracted to it, and are forced to stay the night before being allowed to depart in the morning, laden with pollen. Finally, Attenborough introduces the world's largest inflorescence: that of the titan arum.