Many citizens around the globe believe conspiracy theories. Why are conspiracy theories so appealing? Here, we propose that conspiracy theories elicit intense emotions independent of emotional valence. People therefore find conspiracy theories entertaining – that is, narratives that people perceive as interesting, exciting, and attention-grabbing – and such entertainment appraisals are positively associated with belief in them. Five studies supported these ideas. Participants were exposed to either a conspiratorial or a non-conspiratorial text about the Notre Dame fire (Study 1) or the death of Jeffrey Epstein (preregistered Study 2). The conspiratorial text elicited stronger entertainment appraisals and intense emotions (independent of emotional valence) than the non-conspiratorial text; moreover, entertainment appraisals mediated the effects of the manipulation on conspiracy beliefs. Study 3 indicated that participants endorsed stronger conspiracy beliefs when an election event was described in an entertaining rather than a boring manner. Subsequent findings revealed that both organisational (Study 4) and societal conspiracy beliefs (Study 5) are positively associated with sensation seeking – a trait characterised by a preference for exciting and intense experiences. We conclude that one reason why people believe conspiracy theories is because they find them entertaining.