What is QAnon? The origins of the bizarre conspiracy theory claiming Trump-Russia investigation is a hoax to catch paedophiles

If QAnon's claims were true, they would shake the very foundations of global government and explain the confusion of politics in recent years. As it is, they are not true – but their importance could nonetheless be hugely significant. It might have been destined to stay as an underground conspiracy theory. But it has quickly taken root both online and off – becoming a feature of Trump rallies and being shared by some of the most important people in the media. It is undeniably dark: it accuses some of the most powerful people in the world of some of the most heinous crimes.