Indeed, that's Andrew Wiles, or now Sir Andrew Wiles KBE FRS Royal Society Research Professor at the University of Oxford. It's likely this was the documentary:

Indeed, that's Andrew Wiles, or now Sir Andrew Wiles KBE FRS Royal Society Research Professor at the University of Oxford. It's likely this was the documentary: https://www.bbc.co.uk/iplayer/episode/b0074rxx/horizon-19951996-fermats-last-theorem https://www.bbc.co.uk/iplayer/episode/b0074rxx/horizon-19951...