Still living with her mother and working as a temp, Becky compares herself to the picture-perfect lives on Instagram, compulsively returning to one account: Chloe's (Gilbert). Becky obsessively watches her seemingly flawless life through social media. But when Chloe dies suddenly, Becky's need to find out how and why leads her to assume a new identity and engineer a "chance" meeting with Chloe's best friend, Livia (Bennett-Warner), and infiltrate Chloe's group of close-knit friends. Through her alter-ego Sasha, Becky becomes a powerful, transgressive heroine; a popular, well-connected "someone" with a life, and loves, that are far more exciting and addictive than the "no one" she is as Becky. However, the pretense soon obscures and conflates reality, and Becky risks losing herself completely in the game she is playing.