Athena challenges Milo's ethics and is shocked when he reveals his real plan. Mia's surprise return has ramifications for the Hawkins family. Mattie finds Leo but can she trust him with her secret? Max resolves to begin a new community of Synths; when he learns how far Leo is prepared to go to complete his mission, he takes matters into his own hands.
Elenco: Gemma Chan , Colin Morgan , Katherine Parkinson , Tom Goodman-Hill , Lucy Carless , Emily Berrington , Theo Stevenson , Ivanno Jeremiah , Pixie Davies , Will Tudor , Sope Dirisu , William Hurt , Carrie-Anne Moss , Ruth Bradley .