Months after saying goodbye to sentient synth Mia (Gemma Chan, Fantastic Beasts and Where to Find Them) and her family, the Hawkinses search for some semblance of normalcy. Laura (Katherine Parkinson, The IT Crowd) and Joe (Tom Goodman-Hill, Mr. Selfridge) attend marriage counseling, even as they grow concerned over their daughter's (Pixie Davies, Miss Peregrine's Home for Peculiar Children) strange behavior. But when Niska (Emily Berrington, 24: Live Another Day) arrives at their home unannounced, the family is pulled back into the dangerous lives of the synths. As synths begin to gain consciousness all over the world, a mysterious organization starts hunting them down. Leo (Colin Morgan, The Fall) and Max (Ivanno Jeremiah, Black Mirror) clash over how to protect the self-aware synths, while a renowned AI scientist (Carrie-Anne Moss, The Matrix trilogy) joins a global tech company preparing to release a revolutionary new product.