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Season 2 episode 1.
"Be Right Back"
The episode tells the story of Martha (Hayley Atwell), a young woman whose boyfriend Ash Starmer (Domhnall Gleeson) is killed in a car accident. As she mourns him, she discovers that technology now allows her to communicate with an artificial intelligence imitating Ash, and reluctantly decides to try it. "Be Right Back" had two sources of inspiration: the question of whether to delete a dead friend's phone number from one's contacts, and the idea that Twitter posts could be made by software mimicking dead people.
"Be Right Back" explores the theme of grief; it is a melancholy story similar to the previous episode, "The Entire History of You". The episode received positive reviews, with the performances of Atwell and Gleeson receiving universal acclaim. Some critics believe it to be the best episode of Black Mirror, though the ending was met with criticism. Several real-life artificial intelligence products have been compared to the one shown in the episode, including a Luka chatbot that was partially inspired by the episode, and a planned Amazon Alexa feature designed to imitate dead loved ones.