NOVA investigates the story of cannabis from the criminalization that has disproportionately harmed communities of color to the latest medical understanding of the plant. What risks does cannabis pose to the developing brain? How much do we know about its potential medical benefits? As cannabis becomes socially accepted and state-legalized, scientists are exploring its long-term health consequences.

Join scientists on the most ambitious Arctic research expedition of all time. Experts from over twenty different nations join the voyage of the massive Polarstern icebreaker as it's gripped by the polar ice and drifts for nearly an entire year. From this unique research station, they can make long-term observations and perform experiments in unprecedented detail. Facing hungry polar bears, perilous sea ice cracks, and brutal cold, the team strives to understand the forces changing the region—and the world—forever.