A love story does not usually involve the plotting of a main character’s death so other characters can live happily together. However, Charlie Stratton’s “In Secret” does, but despite these elements, the film manages to retain the sense of an epic love saga through striking performances, delicate plot twists and an extremely captivating story.

“Secret,” in theaters Feb. 21, is based on Emile Zola’s 1867 novel “Thérèse Raquin.” The movie tells the story of the young, sexually-repressed Thérèse (Elizabeth Olsen). Her overbearing aunt Madame Raquin (Jessica Lange) has arranged for her to marry her sickly cousin Camille (Tom Felton).

When the family moves to Paris, Thérèse’s life remains dull until she meets Laurent (Oscar Isaac), a childhood friend of Camille’s. Laurent and Thérèse soon discover a sexual tension between them that cannot be suppressed. The lovers do everything in their power to be together, even when it means bringing harm to their loved ones.

This story is brought to life by the magnetic presence of the actors. Indie queen Olsen shines as Thérèse, communicating a persistent yet restrained lust for life and love. While Felton’s sniveling man-child is easy to dislike, the actor compels the audience to pity his character’s inability to express real passion.

However, Laurent has no problem showing passion. Isaac grounds his performance of this devil-may-care role in the shadow of a love that the members of the audience can feel themselves. Lange’s presence is felt throughout the film. Her incredible talent showcases itself in her ability to command the screen, even when her character remains silent.

The film is carried along by the surprisingly intoxicating love between Laurent and Thérèse, but even more shocking is the pity the audience feels for Camille. Rather than supporting the star-crossed lovers, viewers watching “Secret” hesitate to accept Thérèse’s relationship with Laurent.

This uncertainty is displayed in the portrayal of Thérèse. Camille does his best to woo Thérèse, but he does not court his fiancee in the sensual way she desires. Thérèse craves passion in her life and decides that only a relationship with the brooding Laurent can satisfy that craving.

Laurent and Thérèse’s relationship grounds the film in a believable reality as the couple discovers the sensual desires of forbidden romance. Olsen and Isaac execute these trysts with the excitement of a first love as they foreshadow their characters’ future adventures together.

With all of its tense romantic politics, “In Secret” does not have a happy ending. The audience will not leave convinced of the beauty in risking everything for love. Yet the resolution still feels justified, signifying that a narrative does not need a cliche ending to make viewers feel a sense of wholeness.

A version of this article appeared in the Feb. 19 print edition. Laura Wolford is a staff writer. Email her at [email protected].