Callum grew up on the Knoll Estate on the outskirts of Brighton and Hove. A career in journalism had never occurred to him – his goal was to train as a PE teacher and become a professional football referee. But the cost of tuition fees put paid to that and at just 18 Callum started work at Brook House Immigration Removal Centre. He found it awash with abuse, self-harm and violence. Tempted to resign, he decided instead to write to Panorama and the rest, as they say, is history.

Callum became a whistle-blower and undercover reporter for the BBC and his footage was the centerpiece of the 2018 RTS award-winning Panorama ‘Undercover: Britain’s Immigration Secrets’. As we go to press the programme has also been nominated for a BAFTA. In 2017 Callum received a Liberty Human Rights Award in recognition of his work.