In “Between Two Worlds,” Juliette Binoche portrays Marianne Winckler, a woman facing financial hardships in Normandy, France. Upon arriving at an unemployment center, she appears shy and bewildered, emphasizing her ability to work effectively in a team to secure a minimum wage job.

Through a voice-over, the director Emmanuel Carrère unveils the true significance of this social-justice drama: Marianne, an investigative journalist, has gone undercover. Her mission is to expose the exploitation of low-income workers, particularly women working night shifts under contracts with private sanitation companies.

The film is loosely based on “The Night Cleaner” (2010), the bestselling nonfiction book by Florence Aubenas, a French journalist who lived a double life as a cleaner for an English Channel ferry while conducting her investigation.

Written by Carrère and Hélène Devynck, “Between Two Worlds” deviates from its source material through a fictional arc. Marianne, as a symbolic figure aiming to expose the injustices of the system, also grapples with guilt over concealing her true identity from her co-workers, such as Christèle (Hélène Lambert), a single mother with a rebellious demeanor. This divide is mirrored in the casting choices, as the usually glamorous Binoche stars alongside nonprofessional actors.

Carrère, primarily known in Europe for his nonfiction books with a literary twist, adopts a tone of cool journalistic sobriety to depict Marianne’s shocking discoveries. In one particularly compelling scene, she is compelled to prepare over 100 beds in less than two hours. However, the sentimental crisis resulting from Marianne’s deceit is less captivating. It serves mainly as a reminder that advocacy work often embodies the pitfalls of the main-character syndrome.

Between Two Worlds
Not rated. In French, with subtitles. Running time: 1 hour 46 minutes. In theaters.