Sleep paralysis accompanied by hypnopompic ('upon awakening') hallucinations is an often-frightening manifestation of discordance between the cognitive/perceptual and motor aspects of rapid eye movement (REM) sleep. Awakening sleepers become aware of an inability to move, and sometimes experience intrusion of dream mentation into waking consciousness (e.g. seeing intruders in the bedroom). In this article, we summarize two studies. In the first study, we assessed 10 individuals who reported abduction by space aliens and whose claims were linked to apparent episodes of sleep paralysis during which hypnopompic hallucinations were interpreted as alien beings. In the second study, adults reporting repressed, recovered, or continuous memories of childhood sexual abuse more often reported sleep paralysis than did a control group. Among the 31 reporting sleep paralysis, only one person linked it to abuse memories. This person was among the six recovered memory participants who reported sleep paralysis (i.e. 17% rate of interpreting it as abuse-related). People rely on personally plausible cultural narratives to interpret these otherwise baffling sleep paralysis episodes.