Katherine Waterston has been cast in 'The End We Start From'.

The 42-year-old actress will star alongside Jodie Comer in the apocalyptic thriller that is being directed by Mahalia Belo.

The film is set in London during an environmental crisis and tells the story of a mother (Comer) who tries to find a way home amid chaotic floods with her newborn child. Waterston will play a character known as 'O'.

Benedict Cumberbatch's SunnyMarch company are producing the flick, with the 'Sherlock' star set to executive produce alongside Jodie.

The flick is based on Megan Hunter's "heart-wrenching" novel and Alice Birch has adapted the script for the big screen.

Producers Leah Clarke, Liza Marshall and Adam Ackland have said: "'The End We Start From' is very close to our hearts.

"Megan’s heart-wrenching novel, and Alice’s wonderful adaptation, present a story about motherhood, separation, social and environmental upheaval, and those primal instincts in us which draw moments of joy and inspiration out of the chaos. We are incredibly excited to have Mahalia and Jodie lead this talented creative team in making what we know will be a resonant, riveting film."

Katherine stars as Tina Goldstein in the 'Fantastic Beasts' franchise and confessed that she was taken aback by the commitment that comes with starring in the 'Harry Potter' prequel series.

The 'Logan Lucky' star said: "I really didn't know what I was getting into to be honest. I didn't realise what a different thing a franchise is from a film, you know? The commitment, the duration of the shoot, the duration of the press tours, how much of your year it asks of you."