The COVID-19 pandemic has exposed the vulnerability of knowledge in times of crisis. Various conspiratorial meaning-making narratives have been spread since the pandemic began in 2020 to explain to people why the crisis is happening, but also with the intention of consciously manipulating us. The WHO describes an ‘infodemic’ – in other words, a viral spreading of misleading information – which makes it harder for people to understand the seriousness of the disease and what is needed in order to fight it Conspiracy theories about the origin and spread of the virus, its morbidity and mortality, the political countermeasures, the expertise of public health science and in particular vaccination have influenced and polarised opinion. Conspiratorial ideas about the pandemic not actually existing or being a way of achieving a global dictatorship sow discord and undermine societal and interpersonal trust. Conspiracy theories are a serious threat to Swedish democracy, since they reject or cast suspicion on expertise and state actors, and hasten radicalisation processes. They also prepare the ground for foreign powers’ information influence activities directed at Sweden. There is no doubt that greater knowledge about conspiracy theories is needed within a psychological defence capability.