Hundreds of sub-postmasters were jailed or financially ruined after computers said money was missing from their branches, but the Post Office has admitted that its Horizon system can make mistakes. But when did senior managers find this out, and did they continue to prosecute postmasters for stealing when they knew technology could be to blame? Reporter Nick Wallis investigates what could be Britain's biggest-ever miscarriage of justice scandal and uncovers evidence of a cover-up at the Post Office.

Daniel De Simone investigates a global network of neo-Nazis that aims to destroy society, discovering that it is recruiting in the UK. Police say right-wing extremism is the fastest growing terrorist threat in the UK and that the coronavirus pandemic may be leaving young people vulnerable to radicalisation. As Daniel investigates he notices certain names cropping up again and again and tracks down some of the movement's most influential figures and reveals how the network operates across the globe.