Set in a future where most of air on Earth has become toxic, the majority of survivors have fled off-world to a space station near Io, a space station orbiting the titular moon of Jupiter. The remaining survivors on Earth have fled to live at high altitudes while awaiting transport to IO. However, the evacuation is winding down, with only one shuttle launch remaining before Earth is abandoned fully by humanity.
Sam Walden (Qualley), the daughter of a famed scientist Dr. Harry Walden (Huston), is one of the few remaining survivors on Earth. She and her father live in an outpost on a high-altitude mountain overlooking an abandoned city, and are trying to determine a means by which humans and animals can adapt to Earth's hostile conditions. Sam quickly but finds her priorities confused by the appearance of Micah (Mackie), a traveller in a hot air balloon who is trying to reach her father reach her father and make it to the final shuttle launch.
The film was released in the USA on January 18, 2019, by Netflix.
- After the End: It's been more than a decade since Earth has become almost completely inhospitable to humans, with the lower altitudes covered in a poisonous fog. Most survivors have been able to evacuate to a space station called Io, but the remaining have been eeking out a living at high altitudes while awaiting the shuttles to escape.
- Dead All Along: When Micah comes in search of Dr. Walden, Sam initially tells him that Walden is conducting field research and will return in a few days. Sam eventually discovers that his laboratory hasn't been used in months, and forces Sam to admit that Henry has been dead for some time.
- Go Mad from the Isolation: Mad is a stretch, but Sam has been by herself at her outpost for months, with no one but her boyfriend Elon to talk to by email. She's definitely been alone a bit too long by the time Micah finds her. However, he isn't much better.
- Homeworld Evacuation: The prologue mentioned that as the atmosphere first got bad a few scientist started building a power station to harvest energy from other planets instead, but things got so bad that power station turned into an escape colony orbiting IO, with the people there having little faith in Sam's project and looking for new planets to colonize.
- MayDecember Romance: Micah is about twenty years older than Sam.
- Race Against the Clock: At the start of the movie, the final shuttle to Io is scheduled to launch in 3 days time. Micah is desperate to get to it (Sam slightly less so), but hampered by less than favorable winds, which are needed to fly his balloon. Things get more dire when they learn the launch site has been moved farther away, and they lack the helium necessary for the balloon to fly that far.
- Minimalist Cast: The movie's cast consists of just Sam, Micah, briefly her father and (over the radio) Elon.
- Sole Surviving Scientist: A surprisingly low-tech version of this in the form of Sam Walden (continuing a project started by her dead father, who also broadcast messages urging lingering humans not to leave Earth) who tried to clear out the toxic atmosphere by raising and training bees to pollinate enough oxygen producing plants. By the time Sam succeeds she may be the last person left on Earth and its unclear if anyone else will come back.
- Someone to Remember Him By: A non-fatal version. Sam is seen with Micah's son in the last scene, after he's left Earth and she stayed.
- The Voice: Sam's boyfriend Elon, at IO.