Saoirse Ronan’s new film "Lady Bird" is fresh from its debut at Telluride Film Festival in Colorado and already Oscar buzz about her performance is growing.

The bittersweet coming-of-age drama was written and directed by "20th Century Women" actress Greta Gerwig based on experiences growing up in Northern California. Ronan plays Gerwig’s alter ego Christine 'Lady Bird' McPherson, a high school student desperate to leave home and her strong-willed mother (Laurie Metcalf) for college life and the big bad world.

Variety gushes about Ronan saying her performance "further cements her as one of the great actresses of her generation," while also tipping co-star Metcalf as an Oscar contender in her own right.

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Onscreen Ronan is a revelation – who knew she could nail deadpan comedy? – as a rebellious student at a conservative Catholic high school in Sacramento who dreams of escaping her overbearing family and small town life to go to college in New York.

Gerwig picked Ronan as her first choice for the part and the decision pays off handsomely. The film’s supporting cast includes heavy hitters Laurie Metcalf, Lucas Hedges, Tracy Letts, Timothee Chalamet and Beanie Feldstein.

Ronan will also soon be seen playing the title role in "Mary, Queen of Scots" for Focus Features.

"Mary, Queens of Scots" is the feature directorial debut of Josie Rourke, artistic director of The Donmar Warehouse theatre, and the script is by "House of Cards" creator Beau Willimon, based on John Guy’s acclaimed biography "My Heart is My Own: The Life of Mary, Queen of Scots."

The film is expected to screen in 2018.

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Saoirse Ronan as Christine 'Lady Bird' McPherson in Lady Bird.