After taking residence in a slum building, a young woman meets her neighbor, a frail and flinching old man, who relates to her the tale of how he encountered a monstrous creature from space. Having fled the creature he took up hiding in the tenament, scared to leave his room. When someone knocks on his door, it frightens the man into a heart attack and he dies. The woman he related the tale to then changes form, revealing herself to be the alien, and who had come to finish him off.