Emily Watson is set to join Kristen Bell and Adam Brody in the film Some Girl(s).
The British actress plays Lindsay, a married woman who has been in an affair with Adam's character, according to The Hollywood Reporter.
In Neil LaBute's self-penned adaptation of his stage play, the film follows a man (played by Adam) who revisits several of his scorned ex-girlfriends on the eve of his wedding.
Directed by Jennifer Getzinger, the ensemble cast also includes Jennifer Morrison, Zoe Kazan and Mia Maestro, who will play the other ex-girlfriends.
War Horse star Emily will next be seen alongside Kiera Knightley and Jude Law in Joe Wright's adaptation of Anna Karenina.