Sir David Attenborough tells the stories of the world's best animal architects. There are house-proud bower birds, who only find a mate if they decorate their homes perfectly. There are hornets, who build electric central heating systems, and the star-nosed mole, whose house is designed so well that worms, his favourite meal, literally drop in for dinner. From larders to nurseries and from high-rises to subway systems, Attenborough shows that the animal architects have designed it long before humans.
The era of the sabretooth and many other Pleistocene creatures comes to an end. The biggest big cats ever, the lion and the tiger, become the kings of their respective habitats - but they had to fight for their place. To survive, these great cats target larger and more challenging prey.
There's a whole world, and more than one spectrum of sensations that animals are aware of, which surpass humans. There's a kind of "sixth sense" that some animals have, which still defies explanation. Call it extra-sensory perception animal abilities we can't entirely explain.