Extinct (2016)

In a post apocalyptical world ridden of all human life, an unknown race has changed the atmospheres natural gas to a breathable one for their respiratory system. In this mystery sci-fi, Extinct follows young Felicity Walker and her brother Archibald on a twisted adventure to maintain their survival. Along with four other unfortunate stranded survivors, they must seek refuge in a safer terrain. Little does the group know that Felicity and her brother have grown immunity to the intruder's gas. After a message is received from their supposed deceased father, the survivors decide to locate him deep in intruder's territory. The now torn group ventures forth into an alien ambush. After discovery of Felicity and her brother secret the extraterrestrials capture both of them and leave the others to die.