John Ioannidis is one of the most published and influential scientists in the world, someone whose skewering of bad medical research we at SBM have frequently lauded over the years. Then the COVID-19 pandemic hit. Since then, Prof. Ioannidis has been publishing dubious studies that minimize the dangers of the coronavirus, shown up in the media to decry “lockdowns,” and, most recently, “punched down”, attacking a graduate student for having criticized him. What happened? Did Prof. Ioannidis change, or was he always like this and I just didn’t see it? Either way, he’s a cautionary tale of how even science watchdogs can fall prey to hubris.