David Attenborough has a passion for birds' eggs. These remarkable structures nurture new life, protecting it from the outside world at the same time as allowing it to breathe. They are strong enough to withstand the full weight of an incubating parent and weak enough to allow a chick to break free.

But how is an egg made? Why are they the shape they are? And perhaps most importantly, why lay an egg at all? Piece by piece, from creation to hatching, David reveals the wonder behind these miracles of nature.

The peregrine falcon is the fastest animal on earth - it can reach speeds of over 200mph. But what does it take to be a high-speed record breaker? To find out, we follow a young family of falcons as they grow up in downtown Chicago. We join renowned bird handler Lloyd Buck, who, with the help of state-of-the-art technology and leading avian scientists, puts his peregrines to the test. And finally, we see if Lloyd can train one young peregrine for the ultimate challenge of speed and agility - against an Olympic skier in the Swiss Alps. Through such groundbreaking experiments and intimate views of these special birds in the wild, the secrets behind these super-fast falcons can finally be revealed.