Directed by Sebastián Silva. Starring Catalina Saavedra, Claudia Celedón, Mariana Loyola, Alejandro Goic, Anita Reeves, Delfina Guzmán TBC cert, limited release, 95 min

THE DERANGED servant is a much-explored phenomenon in cinema. Consider Judith Anderson scowling at Joan Fontaine in Alfred Hitchcock's Rebecca. Think of Dirk Bogarde sneering at James Fox in Joseph Losey's The Servant. Matured in Marxist compost, nourished by Freudian irrigation, such relationships offer film-makers any number of sinister possibilities.

This low-budget Chilean feature – battered and washed-out in appearance – manages to uncover some fresh twists on the formula.

Sebastián Silva’s film focuses on an achingly bourgeois family living in the suburbs of Santiago.

Mum spends her days praying, supervising the help and entertaining her judgmental mother. Dad plays golf and works on an ornate model sailing ship (just as Chekov’s gun over the hearth must eventually be brandished, Silva’s delicate vessel seems certain to come to a sticky end). The teenage children do what teenage children will.

For the last two decades, Raquel, the family’s maid, has maintained reasonably harmonious relations with the household, but, just recently, she has started to behave abnormally. She has fainting spells. Her temper is frayed.

When her employers, initially understanding and tolerant, hire some help – first a timid Peruvian, later a wire-haired harridan – she spins even further out of control.

She locks her colleagues out of the house. When they take a shower, she scrubs the bathroom clean with disinfectant. Such is the furrowed inscrutability of Catalina Saavedra’s splendid performance that we are never certain how far down the path to madness Raquel has progressed.

At times, we seem to be enduring a detailed portrait of a nervous breakdown (triggered, perhaps, by over-exposure to cleaning products). At others, the picture appears to be veering into thriller territory.

Ultimately, however, the film-makers wrong-foot the viewer by turning back from melodrama and inviting the viewer to accept Raquel as a fleshy, nuanced human being.

Mildly satirical, occasionally blackly hilarious, The Maidends up operating within its own agreeably peculiar genre.