Erin Doherty (The Crown), Billy Howle (The Serpent), Pippa Bennett-Warner (Gangs of London) and Jack Farthing (Poldark) will star in the six-part series exploring obsession, deceit, identity and grief.

Also joining the talented young cast will be Poppy Gilbert (Stay Close), Akshay Khanna (Grace), Brandon Micheal Hall (Search Party) and newcomer Alexander Eliot.

Doherty will lead the series as Becky, a young woman working as a temp and still living with her mum who develops an unhealthy obsession with the picture-perfect life Chloe (Gilbert) projects via her Instagram account.

When Chloe dies unexpectedly, Becky assumes a new identity and engineers a ‘chance meeting’ with Chloe’s best friend, Livia (Bennett-Warner) to discover what happened to her.

Through her new alter-ego Sasha, Becky has the chance to transform herself into a popular ‘somebody’ with a far more exciting and addictive life than the ‘nobody’ she was before. As she infiltrates Chloe’s close-knit friends, her new life begins to obscure reality and threatens to trap Becky completely in the dangerous game she is playing.

Creator and writer Alice Seabright, who has previously directed Sex Education, commented: “Becky is a complex, courageous heroine and there is no one better to play her than Erin. All these characters have been a dream to write, and it now feels like they’ve found their soulmates in our amazing cast. I can’t wait to start bringing the show to life with them, and with our wonderful crew. Thank you to the BBC and Amazon, to our brilliant writers, Kayleigh Llewellyn, Poppy Cogan, and Bolu Babalola, and to my partners in crime - the powerhouses Tally Garner and Morven Reid.”

Chloe has started filming in Bristol and will air on BBC One and iPlayer in the UK and on Amazon Prime internationally.