Gardner Elliot (Asa Butterfield) just wants to be on Earth. Gardner is a 16-year-old boy who lives on Mars. His mother, Sarah Elliot (Janet Montgomery), an astronaut on a four-year trip to Mars, finds out she’s pregnant shortly after they arrive. When she dies during childbirth, Gardner is left in the care of a team of scientists. We never learn what became of the other astronauts on the trip who knew the truth about how Sarah died, a truth NASA kept from the public citing a malfunction instead. After we learn of her passing, the movie cuts to Gardner at 16 who is a bit mischievous and desperate to be around someone who is his own age.