Episode One: Numbers
In this first episode, Marcus reveals how significant numbers apear throughout the natural world. They're part of a hidden mathematical world that contains the rules that govern everything on our planet and beyond.
Episode Two: Shapes
Marcus du Sautoy uncovers the patterns that explain the shape of the world around us. Starting at the hexagonal columns of Northern Ireland's Giant's Causeway, he discovers the code underpinning the extraordinary order found in nature - from rock formations to honeycomb and from salt crystals to soap bubbles.
Marcus also reveals the mysterious code that governs the apparent randomness of mountains, clouds and trees and explores how this not only could be the key to Jackson Pollock's success, but has also helped breathe life into hugely successful movie animations.
Episode Three: Prediction
Professor du Sautoy's odyssey starts with the lunar eclipse - once thought supernatural, now routinely predicted through the power of the code. But more intriguing is what the code can say about our future.
Along the path to enlightenment, Marcus overturns the lemming's suicidal reputation, avoids being crushed to death, reveals how to catch a serial killer and discovers that the answer to life the universe and everything isn't 42 after all - it's 1.15.
The Code was first shown on BBC Two in July 2011, and has subsequently been repeated on the Eden channel.
For further details about the series, please visit the BBC Code webpages
Can you buy The Code?
The Treasure Hunt archive
As part of The Code, the BBC team launched a treasure hunt - inviting people to play games to reveal clues. Although the games are no longer available online, we're leaving the tips online as they can help you apply maths skills to similar games...