Although the caption flashes ‘based on real events’ at the beginning of André Téchiné’s French Riveria, nothing can prepare us for his interpretation of the Agnès Le Roux case. This sinister and bizarre real-life story – which began in 1976 and spans over thirty years – is an intriguing, chilling portrayal of manipulation and of events that darkened the usually romanticized and glamourized location of Nice.

Catherine Deneuve is the regal Renée Le Roux, owner of the Casino Le Palais de la Méditerranée, who prowls her glittering golden den (where nobody appears to be under fifty years old) like a grand Lioness. Everything in this gleaming, regal, shiny world begins to tarnish after the arrival of her daughter Agnès (Adèle Haenel), an unchained, young divorcée who has returned home after spending five years in Africa. As soon as her mother’s ‘advisor’ Maurice Agnelet (an understated but chilling performance from Guillaume Canet) collects her from the airport they have chemistry. Yet this chemistry, if wrong, can be extremely toxic and this one omits vapors that are unstable, dangerous and deadly, and will have repercussions that last a lifetime.

Despite warning Agnès “don’t believe what people tell you about me,” Agnelet is distinctly difficult to read and somewhat elusive; his defining characteristics being that “he has many lovers” and is separated from his wife (a lie). Although he acts as Madame Le Roux’s consiglieri with her best interests at heart, his lustre of law-abiding citizen soon fades and we are left with his greedy, manipulative character that would betray his past loyalties in his pursuit of wealth and power. He convinces Agnès to befriend local mob boss Fratoni for the sum of her inheritance, an action that has sinister repercussions that are dramatically felt by both women, culminating in Agnès’s disappearance in 1977 and a lifetime of unresolved torment for Madame Le Roux.

The mother-daughter relationship is particularly interesting – extremely fraught but unconditional – while Deneuve’s fall from high stakes Madame to a broken, frail, shell of a woman seeking justice, is extremely affecting. Canet’s original charming, inoffensive exterior is captivating as he contorts into the faceless manipulator who will stop at nothing in pursuit of glory, while Haenel makes a convincingly unstable woman who has been rejected by her lover hovering on the brink of despair.

Usually filmed with azure sea and sky the film’s murky colour palette works as a reflection of the unsettling true-life events. Anything based on truth will be guilty of favouring particular phases of the story over the others so it is unfortunate that the last part of the film – from the disappearance of Agnès to the final court case and closing credits – feels rather rushed. In spite of this French Riviera is intriguing and engrossing; a dark hearted exposé of deception and greed on the Cote d’Azur where a woman would stop at nothing to secure her daughter’s justice.