A wide-ranging conspiracy theory about elite Satan-worshiping paedophiles has migrated from the US, inspiring a series of regular street protests. How did QAnon find a British audience? On a sunny day in late August, nearly 500 people gathered in central London. It was the first event held by a new group, Freedom for the Children UK. As the crowd marched from the London Eye to Buckingham Palace, chants of "Save our children!" echoed in the air. The ethnically diverse crowd was made up mostly of young people and women, some with their children. At the head of the march were group leaders Laura Ward and Lucy Davis. Ms Ward, 36, who says she underwent a "spiritual awakening" during the Covid-19 lockdown, created a Facebook group in July "to promote and organise peaceful events that raise the awareness of child exploitation and human trafficking". It took off, gathering thousands of followers in just a few weeks. The London march was just one of 10 rallies held across the UK, including events in Birmingham, Bristol and Manchester. A Liverpool rally drew similar numbers of people. The organisers say their movement is not directly linked with QAnon, a wide-ranging, baseless, pro-Trump conspiracy theory. But their themes are similar, and their evidence-free claims largely the same. And when images began to appear on the FFTCUK Facebook group later that day, placards, signs and items of clothing directly referencing QAnon were prevalent at almost all of the rallies. What is QAnon? QAnon began life - most likely as a joke or prank - on extreme message boards in 2017. It's an unfounded conspiracy theory that claims President Trump is secretly battling a clandestine network of Satan-worshipping elites who run a child trafficking ring. The "Q" in QAnon is the person or persons writing cryptic messages to the movement's followers. Q claims to have top secret clearance within the US government. Q has told followers to "trust the plan" for a "great awakening". The messages have predicted mass arrests or purges of top Democratic Party officials. And none of the prognostications have come true. Despite its bizarre premises, QAnon took off in niche online communities and rapidly grew on social networks.