Two robotic missions anchor this film: the Mars Exploration Rovers, Spirit and Opportunity, and the Cassini-Huygens spacecraft sent to Saturn's moon Titan. Engineers and mission scientists explain how you fly a machine you can never touch again once it launches, from the seven-minute blackout of a Mars landing to the light-delay of commands reaching Saturn, where a single instruction takes over an hour to arrive. Archival mission control footage and animations of the spacecraft's approach sequences show how teams plan every maneuver years in advance, then wait to find out if it worked. The rovers' search for evidence of ancient water on the Martian surface runs alongside Cassini-Huygens' descent through Titan's thick atmosphere, the first landing on a moon in the outer solar system. The film stays close to the engineering problem underneath both missions: building hardware that has to work perfectly, unsupervised, a billion miles from anyone who could fix it.