‘Therese Raquin’ review: Keira Knightley kills in dreary adaptation

The show may be grim and overwrought, but 30-year-old film actress Keira Knightley deserves a lot of credit for making her Broadway debut in a new adaptation of Émile Zola’s once incendiary, emotionally charged 1867 novel “Thérèse Raquin,” which is being produced by Roundabout Theatre Company at Studio 54.

A tale of illicit romance, murder and psychological torture, it observes Thérèse (Knightley), a silent but intense young woman who — after being married off by her caretaker aunt, Madame Raquin (Judith Light), to her enfeebled and self-absorbed cousin Camille (Gabriel Ebert) — begins an affair with Camille’s carefree friend Laurent (Matt Ryan).

When the pair are no longer able to meet for their secret afternoon rendezvous, they plot to win back their life together by murdering Camille. Laurent’s plan is to push Camille out of a rowboat and leave him to drown. But once the deed is done, Thérèse and Laurent lose their sexual spark and find themselves haunted by Camille’s memory.

Although Madame Raquin soon learns of their complicity, she somehow loses the ability to speak or move any part of her body except her eyes, making her completely dependent upon the care of her son’s murderers.

Despite elaborate production values, an eerie tone and strong performances, this proves to be a slow-paced and dreary adaptation. The novel’s close-up, ultra-naturalistic depictions of the characters gets lost onstage.

Knightley is at her best when communicating the title character’s stresses and strains through her body language. Ebert, who won a Tony for “Matilda,” adds a much-needed dose of humor in portraying Camille like a spoiled child. Most compelling is Light, especially when she desperately tries to communicate her son’s murder despite her overwhelming physical disability.