Harry Shukman led a double life. Friends and family knew him as a journalist, but unbeknownst to them he was secretly infiltrating the British far right. Equipped with a hidden camera, he posed as ‘Chris’ and set out to expose right-wing extremists.

From canvassing with Britain First to befriending Holocaust deniers, neo-Nazis and a Silicon Valley-backed race-science organisation, Shukman again and again risked his safety and sanity to remove the far right’s terrifyingly everyday mask.

Now, we must ensure it stays off.