Asa Butterfield plays a Martian. Or rather, he’s human, born on our first colony on Mars (in 2018! — optimistic), whose existence is classified (to avoid bad PR) and who, aged 16, decides it’s time to go to Earth even though the different gravity may kill him. Once there he breaks out of quarantine to meet his intergalactic Skype girlfriend Tulsa (Robertson). Playing fast and loose with science (there’s real-time video conferencing over 54.6 million km of space) and logic, it’s an often eye-rolling ride as the youngsters’ passion for each other grows amid a road trip and some gentle culture-shock comedy. But this type of teen melodrama has been done so much better before.