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Zero to Infinity

S49 E19 / 53m 32s / TV-PG
Zero and infinity. These seemingly opposite, obvious, and indispensable concepts are relatively recent human inventions. Discover the surprising story of how these key concepts that revolutionized mathematics came to be – not just once, but over and over again as different cultures invented and re-invented them across thousands of years.
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Crypto Decoded

S49 E18 / 53m 22s / TV-PG
From Bitcoin to NFTs, crypto is making headlines. But what exactly is it, and how does it work? Experts go beyond the hype and skepticism to unravel the social and technological underpinnings of crypto – exploring how it came to be and why this new technology may change more than just money.
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Nazca Desert Mystery

S49 E17 / 53m 31s / TV-PG
One of the world’s greatest ancient enigmas, the Nazca lines are a dense network of criss-crossing lines, geometric shapes, and animal figures etched across 200 square miles of Peruvian desert. Who created them and why? Ever since they were rediscovered in the 1920s, scholars and enthusiasts have raised countless theories about their purpose.
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Ocean Invaders

S49 E16 / 53m 32s / TV-PG
Lionfish–long prized in home aquariums–have invaded the Atlantic, and are now one of the ocean’s most successful invasive species, wreaking havoc in waters across the globe. Join ocean explorer Danni Washington on a journey to find out how they took over, why they’re doing so much damage, and what can be done about it.
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Can Psychedelics Cure?

S49 E15 / 53m 47s / TV-14
Hallucinogenic drugs—popularly called psychedelics—have been used by human societies for thousands of years. Today, scientists are taking a second look at many of these mind-altering substances – both natural and synthetic – and discovering that they can have profoundly positive clinical impacts, helping patients struggling with a range of afflictions from addiction to depression and PTSD.
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Computers v. Crime

S49 E14 / 53m 30s / TV-PG
In police departments and courts across the country, artificial intelligence is being used to help decide who is policed, who gets bail, how offenders should be sentenced, and who gets parole. But is it actually making our law enforcement and court systems fairer and more just? This timely investigation digs into the hidden biases, privacy risks, and design flaws of this controversial technology.
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Ending HIV in America

S49 E11 / 53m 33s
Almost 40 years after the discovery of HIV, could we be on the verge of ending the AIDS epidemic in America? How did scientists tackle one of the most elusive deadly viruses to ever infect humans? Can innovative drugs bring new infections to zero?
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Ultimate Space Telescope

S49 E10 / 53m 33s / TV-PG
Follow the dramatic story of NASA’s James Webb Space Telescope – the most complex machine ever launched into space – in hopes of peering deeper back in time than ever before and answering some of astronomy’s biggest questions.
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Determined: Fighting Alzheimer's

S49 E5 / 53m 28s / TV-PG
Follow three women at risk of developing Alzheimer’s as they join a groundbreaking study to try to prevent the disease – sharing their ups and downs, anxiously watching for symptoms, and hoping they can make a difference.
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Augmented

S49 E4 / 1h 25m
Follow the dramatic personal journey of Hugh Herr, a biophysicist working to create brain-controlled robotic limbs. At age 17, Herr’s legs were amputated after a climbing accident. Frustrated by the crude prosthetic limbs he was given, Herr set out to remedy their design, leading him to a career as an inventor of innovative prosthetic devices.
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Great Mammoth Mystery

S49 E3 / 53m 26s / TV-PG
Sir David Attenborough investigates a unique site in southern England where amateur fossil hunters uncovered giant mammoth bones and evidence of Neanderthals. A team of paleontologists and archaeologists soon discover that the site preserves rare evidence of the extinct beasts and early human inhabitants of Britain dating to over 200,000 years ago.
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Secrets in the Scat

S49 E2 / 53m 32s / TV-PG
Scott Burnett is “Scatman”—an Australian ecologist on the trail of the secrets of poop. By identifying and analyzing animal scat for DNA and hormones, he discovers essential details of their behavior, how they fit in the ecosystem, and even how to protect them.
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Arctic Sinkholes

S49 E1 / 53m 28s / TV-PG
Colossal explosions shake a remote corner of the Siberian tundra, leaving behind massive craters. In Alaska, a huge lake erupts with bubbles of inflammable gas. Scientists are discovering that these mystifying phenomena add up to a ticking time bomb, as long-frozen permafrost melts and releases vast amounts of methane, a potent greenhouse gas.
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