In C.J. “Fiery” Obasi’s Mami Wata, black becomes a canvas onto which the director paints a propulsive and vivid narrative. The shade takes on new roles and meanings in this feature about brewing ideological differences in a fictional West African village. Black shadows the waves crashing the shores as one character contemplates the fate of her people. Black sharpens the designs drawn in white paint on the faces of villagers. Black portends the sinister, the vengeful, the hopeful and the renewed faith swirling within an allegory for the slow creep of modernity.

The film takes place in Iyi, the village where Mami Wata, the water deity of West Africa and its diaspora cultures, has reigned via her intermediary Mama Efe (Rita Edochie) for decades. Obasi begins his wily, supernatural tale with generational tension: Mame Efe’s daughter Zinwe (Uzoamaka Aniunoh) storms out of their home after her mother responds to a village woman’s pleas with vague sentiments about the balance of things. Zinwe doesn’t understand why her mother won’t use her powers to help the woman; her mother tries to explain the rituals by which they must abide.

Amidst this mother-daughter quarrel, a quiet anxiety has taken root within the village. The people of Iyi are losing faith in Mama Efe and, more generally, in the goddess Mami Wata. Obasi, who has made two other features and is a part of a new wave of Nigerian filmmakers who are stretching conceptions of Nollywood, has a knack for storytelling. Mami Wata maintains a steady narrative and balances its broader thematic interests — intergenerational anxiety, Western influence agitating established customs — with action and character development. The entire film is in Pidgin English, which brings a touch of melody to an already poetic piece.

Opposite Zinwe is her adopted sister, Prisca (Evelyne Ily Juhen), who is more reserved about questioning their mother’s commitment to tradition. While Zinwe struggles with Mama Efe, Prisca lives her life — cavorting with a man who has been eyeing her and dancing into the morning at a local bar. She embodies an unforced free-spiritedness and a refreshing sensuality. Through these three central characters, Obasi portrays the dimensionality of women living in a matriarchy and invokes the multitudinous meanings of Mami Wata, a famously mercurial deity.

Edochie plays Mama Efe as a stoic presence in the village, a woman unfazed by the changes happening among her people. Zinwe is a sharp contrast to her mother, and Aniunoh emphasizes the young woman’s easily disturbed temperament. Juhen’s Prisca falls somewhere in the middle of these divergent women. She sways between her mother and sister, trying to grasp and join bits of each of them.

Mami Wata is told in chapters, with each section introduced by a title card. The action takes off in the third part when a man named Jasper (Emeka Amakeze) washes up on the village’s shore. Prisca and Mama Efe — now alone since Zinwe ran away — nurse the stranger back to health and welcome him into their inner circle. Meanwhile, unrest continues in the village as a mysterious illness starts spreading. One resident, Jabi (Kelechi Udegbe), forms a rebel group that demands Mama Efe cede control of the village to them.

Conflict soon erupts in the village as Jabi and his crew gain control. Betrayals are revealed too, as Prisca learns more about Jasper and his murky past. These heightened stakes help Mami Wata fulfill its genre aspirations. As Prisca tries to save her village, Obasi’s film moves away from its more observational beginning and embraces the compelling beats of a conventional thriller.

Similar to the work of Nigerian artist Toyin Ojih Odutolah, with whom Obasi shares national origins, Mami Wata recasts familiar stories in newly energizing ways and experiments visually with black, white and the grays between them. The film revisits well-trodden threads of tension in narratives from postcolonial nations like Nigeria —  the creeping violence of colonization, the pull of self-determination — and tries to ask different questions and imagine alternatives. At first Jabi and his crew seem like the answer to the villagers’ mounting issues, but power corrupts the rebel group, who ultimately prove unreliable. Should the village, the film then asks, reinstate an intermediary or find another way?

With the help of DP Lílis Soares, whose camerawork received a special jury prize at Sundance, Obasi mimics that exercise visually, pulling more meaning from the shades between black and white. In the charcoal night sky, Obasi and Soares see the mercurial moods of the goddess. In the obsidian forest where Prisca confronts the rebel group, they craft a metaphor for Iyi’s turmoil and identity crisis. And in the onyx-colored waves, crashing against the sandy shores, they find the traditions of the past rubbing up against the siren call of the future.