It begins by examining the shift in the language and sound of music from the melodies and harmonies of giants such as Mozart, Haydn and Brahms into the fragmented, abstract, discordant sound of the most radical composers of the new century - Schoenberg, Webern, Stravinsky and beyond. It examines how this new music was a response to the huge upheaval in the world at the start of the 20th century, with its developments in technology, science, modern art and the tumult of the First World War. Featuring performances of some of the key works of the period, performed by the London Sinfonietta, members of the Aurora Orchestra and composer and pianist Timothy Andres, the story of this episode in music history is brought to life through the contributions of the biggest names in modern classical music, among them Steve Reich, John Adams, Michael Tilson Thomas, Pierre Boulez, George Benjamin and Alex Ross, music critic of the New Yorker.

Rothko is known for his abstract expressionism paintings, but he moved through more traditional styles in his early career, including Surrealist paintings in the 1940s. In 1947 he embarked on the first of his large abstract 'colour-field' paintings, formalising their structure further in the 1950s. Rothko had huge success with largescale solo shows, but committed suicide in 1970.

In this episode, Michael demonstrates how our society is built on our search to find the answer to what makes up everything in the material world. This is a story that moves from the secret labs of the alchemists and their search for gold by the stone of the philosophers to the creation of the world's first synthetic dye - Purple - and onto the invention of the transistor. This quest may seem abstract and highly theoretical. Yet it has delivered the greatest impact on humanity. By trying to answer this question, scientists have created theories from elements to atoms, and the strange concepts of quantum physics that underpin our modern, technological world.