Computers, the Internet and social media enable every individual to be a publisher, communicating true or false information instantly and globally. In the ‘post-truth’ era, deception is commonplace at all levels of contemporary life. Fakery affects science and social information and the two have become highly interactive globally, undermining trust in science and the capacity of individuals and society to make evidence-informed choices, including on life-or-death issues. Ironically, drivers of fake science are embedded in the current science publishing system intended to disseminate evidenced knowledge, in which the intersection of science advancement and reputational and financial rewards for scientists and publishers incentivize gaming and, in the extreme, creation and promotion of falsified results. In the battle for truth, individual scientists, professional associations, academic institutions and funding bodies must act to put their own house in order by promoting ethics and integrity and de-incentivizing the production and publishing of false data and results. They must speak out against false information and fake science in circulation and forcefully contradict public figures who promote it. They must contribute to research that helps understand and counter false information, to education that builds knowledge and skills in assessing information and to strengthening science literacy in society.