The plot begins with Ashley (Arjona) asking her husband, Carey (Marvin), for a divorce. Devastated and struggling to process the situation, Carey seeks support from his married friends Julie (Johnson) and Paul (Covino), who claim the key to a happy marriage is an open relationship. However, things quickly spiral when boundaries are crossed among all four characters, leading to a series of awkward entanglements, physical confrontations, and comedic mishaps.

Splitsville had its world premiere at the 2025 Cannes Film Festival in the Cannes Premiere section on May 19. The Cannes Premiere section is reserved for films the festival wished to include in the main Competition but could not due to limited space. The film is scheduled to open in select U.S. theaters on August 22, followed by a wider national and international release on September 5.

The trailer showcases the gray areas of friendship and marriage, presented through a sharp, fast-paced romantic comedy. It blends humor with high-stakes emotional tension. Dakota Johnson and Adria Arjona lead the ensemble as part of an emotionally tangled group of adults navigating divorce, love, and questionable advice.