The source is a transcript of a conversation aboard a ship where the crew members report sightings of UFOs and a humanoid alien. There is a debate on the validity of these reports, with some crew members believing the stories while others attribute them to misinterpretations and psychological factors. The investigators initially doubt the stories but eventually find plausible explanations for the sightings, including a nuclear submarine, a fog-filled night, seagulls mistaken for flying objects, and a crewman in a masquerade costume.