We are in the grip of an allergy epidemic. 50 years ago one in 30 were affected, but in Britain today it is closer to one in three. Why this should be is one of modern medicine's greatest puzzles. In search of answers, Horizon travels round the globe, from the remotest inhabited island to the polluted centres of California and the UK. We meet sufferers and the scientists who have dedicated their lives trying to answer the mystery of why we are becoming allergic to our world.

Dr Jago Cooper reveals the history of some of South America's ancient civilisations. He begins with an epic journey into the remote Peruvian Andes in search of the mysterious Chachapoya people. Once numbering half a million, they were known as the 'People of the Clouds'. Dr Cooper reveals how they developed sophisticated methods of recording stories, traded in exotic goods found hundreds of miles from their territory, and had funeral traditions that challenge assumptions about ancient human behaviour. His search for evidence takes him to astonishing cliff tombs untouched for 500 years and one of the most spectacular fortresses in South America, where the fate of the Chachapoya is revealed.

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.

As NASA releases the first images from the James Webb Space Telescope, this film tells the inside story of the telescope's construction and the astronomers taking its first picture of distant stars and galaxies. Will it be the deepest image of our universe ever taken? The successor to Hubble, and 100 times more powerful, the James Webb is the most technically advanced telescope ever built. It will look further back in time than Hubble to an era around 200 million years after the Big Bang, when the first stars and galaxies appeared. Webb's primary mission is to capture the faint light from these objects on the edge of our visible universe so that scientists can learn how they formed, but its instruments are so sensitive it could also be the first telescope to detect signs of life on a distant planet.
The James Webb Telescope is an £8 billion gamble on the skills of its engineering team. It’s the first telescope designed to unfold in space – a complicated two-week operation in which 178 release devices must all work - 107 of them on the telescope's sun shield alone. If just one fails, the expensive telescope could become a giant piece of space junk.
From its conception in the late 1980s, the construction of Webb has posed a huge technical challenge. The team must build a mirror six times larger than Hubble’s and construct a vast sun shield the size of a tennis court, fold them up so they fit into an Ariane 5 rocket, then find a way to unfold them in space. This film tells the inside story of the James Webb Space Telescope in the words of the engineers who built it and the astronomers who will use it.

It's a universal dream To soar on wings into the heavens. But it's nothing compared to the reality. Experience our planet as never before: Through the eyes of birds. This is a journey that will embrace the world. A flight across the earth on feathered wings. It's a fantastic voyage following the changing seasons and taking in some of the greatest events on Earth.
Experience a year in the life of our planet from the lush tropics to the frozen North and catch a glimpse of our world as never before: From a bird's-eye view.

Questions are raised about the search for intelligent life beyond the Earth, with UFOs and other close encounters refuted in favor of communications through SETI and radio telescope such as the Arecibo Observatory. The probability of technically advanced civilizations existing elsewhere in the Milky Way is interpreted using the Drake equation and a future hypothetical Encyclopedia Galactica is discussed as a repository of information about other worlds in the galaxy. The Cosmos Update notes that there have been fewer sightings of UFOs and more stories of abductions, while mentioning the META scanning the skies for signals.