The film is being adapted from author Ian MCEwan’s 2014 novel of the same name.

According to Deadline, Thompson will play Fiona Maye, an eminent High Court judge in London, whose marriage to Tucci's American professor Jack, is at breaking point.

In this moment of personal crisis, Fiona is asked to rule on the case of Adam (Fionn Whitehead), the 17-year-old son of Jehovah's Witnesses who refuse a blood transfusion on religious grounds.

The novel and film's title comes from Britain's 1989 Children's Act, legislation which allows authorities to intervene when parents refuse to cooperate with officials to ensure the welfare of their offspring.

FilmNation and BBC Films are co-financing the project, which is being produced by Notting Hill’s Duncan Kenworthy and directed by Notes on a Scandal helmer Richard Eyre.

Filming will take place on location in the British capital from mid-October (16), with Thompson recently revealing she’s already immersed herself in researching the role.

The 57-year-old paid a special visit to Britain's High Court last month (Sep16), were she sat in on a hearing and was even allowed to take the place of the presiding judge on the bench.

According to British newspaper The Times, while in the judge's position she commented, "I feel so powerful up here." When a woman who was at the centre of the ongoing case returned to the courtroom, she was reportedly shocked to see the Academy Award winner apparently taking control of proceedings but said, "I'm a great fan of yours."

An official release date for the film has yet to be announced.