What triggered the incredible diversity of life on Earth, and how have complex life forms, including humans, evolved? Is there direction to evolution? And is human intelligence inevitable? This program focuses on evolution's 'great transformations' —among them the development of a standard four-limbed body plan, the journey from water to land, the return of marine mammals to the sea, and the emergence of humans. Driven by a combination of opportunism and a genetic 'toolkit', these astounding leaps forward define the arc of evolution. And they suggest that every living creature on earth today, and every species that has ever existed, is a variation on a grand genetic theme—a member of one, and only one, tree of life

The film captures de life of Valerie Taylor, a living legend and true pioneer in both underwater filmmaking and shark research. Valerie work has became the basis for much of what we know about sharks today.
Through remarkable underwater archival footage, along with interviews with Valerie herself, 'Playing with Sharks' follows this daring ocean explorer's trajectory from champion spear fisher to passionate shark protector.

Southern Africa is a riot of life and colour because of two great ocean currents that sweep around the continent's Cape. To the east, the warm Agulhas current generates clouds that roll inland to the wettest place in southern Africa. To the west is the cold Benguela current, home to more great white sharks than anywhere else. Moisture laden fog rolls inland, supporting an incredible desert garden. Where the two currents meet, the clash of warm and cold water creates one of the world's most fabulous natural spectacles - South Africa's sardine run. This is the greatest gathering of predators on the planet, including Africa's largest, the Bryde's whale.

Fourth episode examines how plants either share environments harmoniously or compete for dominance within them. Attenborough highlights the 1987 hurricane and the devastation it caused. However, for some species, it was that opportunity for which they had lain dormant for many years. The space left by uprooted trees is soon filled by others who move relatively swiftly towards the light. The oak is one of the strongest and longest-lived, and other, lesser plants nearby must wait until the spring to flourish before the light above is extinguished by leaves. Tropical forests are green throughout the year, so brute force is needed for a successful climb to the top of the canopy: the rattan is an example that has the longest stem of any plant. As its name suggests, the strangler fig 'throttles' its host by growing around it and cutting off essential water and light. Some can take advantage of a fallen tree by setting down roots on the now horizontal trunk and getting nutriment from the surrounding moss and the fungi on the dead bark. The mountain ash (eucalyptus regnans) grows so tall, that regeneration becomes a considerable problem. It is easily flammable, so its solution is to shed its seeds during a forest fire and sacrifice itself. It therefore relies on the periodic near-destruction of its surroundings in order to survive. Attenborough observes that catastrophes such as fire and drought, while initially detrimental to wildlife, eventually allow for deserted habitats to be reborn.

Minerva B is a small rocky planet just like earth, where spacecraft Artemis has found water, organic molecules, and complex creatures. Is there something more to find?
'I am the mind of the spaceship, alone among the stars. 50 years ago, from a planet far away, the planet you call home, I launched. A journey of 28 trillion miles across the yawning time of space to the exoplanet, Minerva B: a small, rocky planet, much like Earth, but orbiting another sun. Here, I have found water, organic molecules, and microorganisms. When the news of my discovery reaches Earth years from now, some of you will be amazed. But others will remain unsatisfied, and you will ask, have I not found animals or birds? Have I not met intelligent life like us? And so, my search continues. I will find life of marvellous complexity, and the traces of a devastating loss.'

From steamy jungles to dry deserts, amphibians have taken their first footsteps onto land using their bizarre life histories to break their ties with the water and invade the earth.
This episode delves into the extraordinary and intimate lives of the soft skinned amphibians. This includes the marsupial frogs, a peculiar species where the father carries his young in pouches and then gives birth. It also features warring giant salamanders over a metre long and show-off newts that offer displays just like underwater birds of paradise.