Question: who plays liam in season 1 of black mirror
Answer: The episode , set in an alternative reality where most people have `` grains '' recording everything they do , see , or hear , and allowing them to play back their memories in front of their eyes or on a screen , tells the story of Liam ( Toby Kebbell ) , a man who starts suspecting that his wife Ffion ( Jodie Whittaker ) might have had an affair .