This article explores an intervention that practises the ‘art of deception’ in the context of biomedical publishing. Specifically, we explore the science hoax aimed at revealing problems in the peer review process. We pose a question – are science hoaxes based on deception ever justified? Drawing on interviews with biomedical scientists in the UK, we identify the issue of trust as the key element in the scientists’ evaluations of hoaxes. Hoaxes are seen by some to increase trust, and are seen by others to damage trust. Trust in science is thus a Protean concept: it can be used to argue for two completely different, and sometimes contradictory, positions. In this case, the same argument of trust was recognizably invoked to defend the hoaxes, and to argue against them.