Conspiracy theories offer simple answers to complex problems by providing explanations for uncertain situations. Thus, they should be attractive to individuals who are intolerant of uncertainty and seek cognitive closure. We hypothesized that need for cognitive closure (NFCC) should foster conspiracy beliefs about events that lack clear official explanations, especially when conspiracy theories are temporarily salient. In Experiment 1, NFCC positively predicted the endorsement of a conspiracy theory behind the refugee crisis, especially when conspiratorial explanations were made salient. Experiment 2 showed that when conspiratorial explanations were made salient, NFCC positively predicted beliefs in conspiracies behind a mysterious plane crash. However, the link between NFCC and beliefs in conspiratorial explanations was reversed in the case of a plane crash with an official, non-conspiratorial, explanation for the accident. In conclusion, people high (vs. low) in NFCC seize on conspiratorial explanations for uncertain events when such explanations are situationally accessible.