Kristin Scott Thomas, Patricia Clarkson, and Cillian Murphy lead the cast of writer/director Sally Potter’s new dark comedy The Party — and PEOPLE has the exclusive first look at the trailer.

The film, which competed at the 67th Berlin International Film Festival and opened in the U.K. in October, follows Scott Thomas as Janet — a politician who has just been appointed to a key position and throws an intimate gathering in her London home to celebrate.

While her home fills with friends played by Clarkson, Murphy, Bruno Ganz, Emily Mortimer and Cherry Jones, Janet’s husband Bill (Timothy Spall) gets ready to spill an explosive secret of his own: he’s leaving Janet for another woman.