Orson Welles narrates this NASA production on the question of life beyond Earth, tying it to his own past: the 1938 "War of the Worlds" radio broadcast that convinced some listeners Martians had actually landed. He revisits that panic as a case study in how people imagine aliens, then turns to what actual science says, bringing in biologist George Wald and astronomer Carl Sagan among other scientists to weigh in on probe results from Mars and the odds of intelligent civilizations elsewhere in the universe. Produced by Drew Associates for NASA, the film mixes archival footage of the Welles broadcast's aftermath with contemporary interviews and mission footage from planetary exploration. Its scientists land on a shared conclusion: given the number of stars and planets in the universe, other intelligent life is not just possible but probable. Welles, working here as narrator rather than performer, keeps the tone measured, letting the scientists carry the argument while he supplies the historical hook that got audiences in the door.