Titan, Saturn's largest moon, gets its first close look through the Huygens probe's descent, and this Open University production follows the mission from launch to landing. Adam Hart-Davies presents, walking through why a moon wrapped in orange haze might hold clues to the chemistry that led to life on Earth. Professor John Zarnecki, who worked on the probe's instrument package, unveils the first panoramic images ever taken from Titan's surface, images scientists had waited years to see. The film goes instrument by instrument through the probe's payload, including a microphone that recorded actual sound on another world for the first time, a detail the scientists clearly still find remarkable. Footage follows the mission team through the descent itself, watching data come in with the kind of tension usually reserved for a launch rather than a landing. This is the first of five parts in the series, laying out the stakes and the hardware before the later episodes get into the findings themselves.