Wicked Little Letters stars Olivia Colman and Jessie Buckley in ...

Olivia Colman doesn't put a foot wrong in this uproarious retelling of the little-known, real-life story of the Littlehampton Libels.

In the early 1920s, a small seaside town in Sussex was rocked by a series of foul-mouthed letters — sent at first to local woman Edith Swan, before finding themselves in the mailboxes of her family and community members.

Edith's neighbour and former friend Rose Gooding was accused of penning the letters. Despite continually professing her innocence, Rose spent some months in jail before detectives traced the unlikely source of the letters.

Wicked Little Letters opens with Edith receiving her 19th expletives-laden missive, in what we find out is just the latest in a series of poisonous letters she's received. Seemingly unwilling to prosecute the case further, she's urged on by her father and the police to point the finger at Rose, setting in motion an unstoppable domino-like chain of events.

The Oscar-winning Colman conveys the warring factions within the character of Edith.(Supplied: StudioCanal )

Colman plays the highly religious, prim and proper Edith with supercilious sanctimony and an uptight air, while Jessie Buckley imbues the lovable Irish town outcast Rose with an irrepressible, rapscallion energy.

Lending the film its emotional heft is Buckley's expert balancing of brash swagger with a very real sense of vulnerability when she's punished for perceived crimes that have nothing to do with the letters.

Jessie Buckley imbues her role, as the lovable Irish town outcast Rose, with an irrepressible, rapscallion energy.(Supplied: StudioCanal )

Cloistered by her deep-seated Catholic upbringing and living a tortured existence under the thumb of her abusive father (Timothy Spall), Edith has little personal agency, but with as little as an upturned eyebrow or crooked smile, Colman conveys the warring factions within Edith.

She wants to live a more unfettered existence like her (former) friend Rose, but she battles with the rigour instilled by her religion and the fear evoked by her father. When she does, on occasion, break free of such expectations, the almost maniacal energy that Colman brings to the role is a joy to behold.

Hugh Skinner (back) stars as the laughably incompetent police officer, with Timothy Spall (next to Colman) as Edith's controlling father.(Supplied: StudioCanal )

As in many small-town English cop dramas, the police force in Wicked Little Letters are a blundering mess — perhaps best encapsulated by Hugh Skinner in his role as the laughably useless Constable Papperwick. Woman Police Constable Gladys Moss (Anjana Vasan) — don't you dare forget the 'Woman' part — is the corrective to their missteps.

Gladys was indeed Sussex's first female police officer, but this distinction is offset by the realities of such a position: relegated to making tea for male police officers; having her professional opinions routinely dismissed; living a nun-like existence (female police officers of the time weren't allowed to marry or have children). Vasan injects the unassuming character with a steely pluckiness and a head for hijinks as she transcends the box she's been placed in.

Anjana Vasan (centre, with Lolly Adefope, left and Joanna Scanlan, right) plays Gladys Moss, who really was Sussex's first 'Woman Police Constable'.(Supplied: StudioCanal)

Sussex in the 1920s is unsurprisingly depicted as a deeply patriarchal world – the miscarriage of justice that plays out finds its victims in the women. Girls who play guitars are shunned. Children are weaponised as pawns against mothers who break the mould. The word "spinster" is bandied about like it's an actual swear word in a film replete with curses and cusses. Having a child out of wedlock is regarded as a bigger sin than writing malicious letters.

But what's more surprising in Wicked Little Letters is the simultaneous inclusion and absence of race. Both Gladys and Rose's partner Bill (Malachi Kirby) were white in real life but are played by people of colour in the film. But this fact is rarely remarked upon in a curiously utopian post-race revisionist history.

Gladys is more obstructed by her sex than her race, while Rose and Bill's interracial relationship in a time of otherwise regressive societal views is never acknowledged.

The historical post-war context of the Littlehampton Libels unfolding alongside the British women's suffragette movement is more expertly invoked. Edith is painted as an exemplar woman when compared to the agitating suffragettes, at a time when "women everywhere are losing their decorum".

Wicked Little Letters ultimately a film about a coterie of unruly women.(Supplied: StudioCanal )

Ultimately, Wicked Little Letters is about a coterie of unruly women – some outwardly so, others only able to express this nonconformity in private. The witch hunt against Rose finds a delightful riposte in the almost magical way that Gladys and her assistants unearth the real culprit.

Wicked Little Letters is nothing groundbreaking or unexpected, but it's an entertaining 100-or-so minutes and a lesson in imaginative swearing: "Foxy ass piss country whore", anyone?

Wicked Little Letters is in cinemas now.