David Pogue sets out on a worldwide quest to find the key molecules and chemical reactions that have paved the way for human civilization, life, and even the universe as we know it. Stream all three episodes of NOVA l PBS' “Beyond the Elements” now on the PBS Video app. | PBS

Peer into the universe’s deep unknowns to explore the mysteries of dark matter and energy. Don't miss "NOVA Wonders, "What's the Universe Made Of?" Now streaming at pbs.org/wgbh/nova/wonders/#universe-made-of | NOVA l PBS