TV
The former Coronation Street star said that she was looking forward to playing the role of one of Anne Lister's lovers in the BBC Two programme.
Lister, played by Maxine Peake, was born in 1791 and was a wealthy Yorkshire landowner and renowned diarist who was open about her sexuality.
According to PA, O'Brien said: "It's based on a true story about a woman who wrote all these diaries in code - they decoded them and found out she was a bit of a saucy lesbian and I play one of her love interests."
The 26-year-old, who left her role as Sarah-Louise Platt on Coronation Street in 2007, said that she had always dreamed of acting in a period drama.
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