Martha Marcy May Marlene, Sean Durkin, 101 Mins (15)

Feel-awkward tales of two women: one recalls sex abuse by a charismatic leader; the other is an alcoholic who tries to reclaim her old high-school beau

Flashbacks haunt Martha Marcy May Marlene

To be honest, there's not that much in common between the two films under review this week, except that they're both about women in trouble; they both contain scenes in which the protagonist freaks out alarmingly during a family-and-friends gathering; and both, in different ways, make you ill at ease. In fact, both offer welcome evidence that there's still the odd American film that dares to venture into genuinely uncomfortable areas.

Martha Marcy May Marlene is the debut feature of writer-director Sean Durkin. The title – probably because of its resemblance to Milly-Molly-Mandy – sounds desperately twee, but it's the name, or names, of a young woman who's no longer entirely sure who she is. Martha (Elizabeth Olsen) has drifted into a community based in a rugged old farmhouse and ruled by a no less rugged charismatic leader, Patrick (John Hawkes). He tells her she looks more like a Marcy May than a Martha; she doesn't realise that in this act of cutesy renaming, he's taking possession of her.

For Patrick's community is a cult – although the word is never used. Under cover of a rural idyll, Patrick has created a regime in which women are his sexual playthings, his abuse sold to them as "spiritual cleansing" in a bogus initiation ceremony.

Summarised this flatly, the story sounds like material for a sensationalist TV movie or documentary. But in Durkin's subtly riveting study, Martha's experience emerges only gradually as she retrieves her memories of what she's been through. Escaping from Patrick's house, Martha takes refuge at the lakeside home of her squeaky-clean, well-heeled older sister Lucy (Sarah Paulson). In between fragmentary flashbacks to commune life – not just abruptly triggered but hair-triggered, so swift are the transitions – Lucy and her English husband Ted (Hugh Dancy) puzzle over Martha's bizarre behaviour, which includes sleeping on the floor, plonking herself on the couple's bed while they're having sex, or declaring herself "a teacher and a leader".

MMMM has its moments of trauma and violence, all delicately handled – this is a horror story of sorts, but almost entirely in eerie pianissimo. It's the gentle tweaks that stick with you – such as the moment when Patrick serenades Martha with a folk ballad. The song is sweet and tender yet, sung by Patrick, it becomes a baleful spell to mesmerise his prey.

Elizabeth Olsen gives Martha an ingénue opacity, making her both fragile and fiercely defiant; her understated performance takes us into Martha's head, sparing the film from having to spell out too much. Paulson makes a sharp foil as the sister who's clearly herself damaged in some ways.

Martha Marcy May Marlene is unnerving not because of what it shows you, but because its lucidity and cleanness of execution – just the right side of antiseptic – create a marvellous sense of creeping unease, especially when it comes to the abrupt, audaciously uncertain ending. All in all, you might recognise a flavour of Michael Haneke: this elliptical piece is surely the most Austrian film that's ever come out of the United States.

A horror story of a different kind is Young Adult, the new collaboration from writer Diablo Cody and director Jason Reitman, and a signally darker proposition than their Juno. In this brazenly sour psychological comedy, Charlize Theron plays Mavis, a 37-year-old who writes "young adult" fiction – a series of novels peddling teenagers fancy lies about an impossibly perfect (and loathsome-sounding) high-school princess. Mavis uses her heroine as a hanger for her idealised self-image; in reality, Mavis is an alcoholic, narcissistic wreck who has never got over her moment of prom-queen glory, and views mere mortals with lofty distaste. Rather than tackle the overdue draft of her next book, Mavis heads to her small Minnesota hometown on a deluded mission to win back her old beau, school sports star Buddy (Patrick Wilson, the peerless specialist in affable stolidity).

It's a premise that sounds like the stuff of many a romcom – but that genre never attempts the pitiless character analysis of Young Adult. Mavis finds a drinking buddy and confidant in old schoolmate Matt (a superbly pithy Patton Oswalt). This self-confessed "fat geek" was never on her radar at school, but now has new credibility in Mavis's eyes because he was famously brutalised by homophobic jocks who left him on crutches and with damaged genitals. That's the sort of bleak territory Young Adult inhabits, and the scenes between Matt and Mavis – in which he first recoils from, then collusively feeds, her universal contempt – are quietly astonishing.

You don't often find such cruel incisiveness in American mainstream comedy, and Young Adult elicits a squirm-inducing discomfort that you more often associate with Mike Leigh or Todd Solondz. Mavis is an astonishing creation by Charlize Theron, mischievously turning her beauty against itself to construct a character who's not entirely unsympathetic, and yet fundamentally horrifying, deluded and incapable of change.

If ever a film lived up to the Seinfeld motto of "No lessons, no hugs", this is it (in fact, there is a climactic hug, but not one we're expecting). It's also a small-town movie with a difference: there's none of the supposedly fond mocking of local eccentrics that usually comes as standard. Young Adult is unusually sympathetic and respectful of the people that Hollywood routinely patronises as supporting colour: it suggests that the happiest, sanest person you could meet might be a small-town mom (Elizabeth Reaser, as Buddy's wife Beth) who plays drums in a creaky but cheerful indie band.

Some might detect misogyny in the film's punishing depiction of Mavis, but it's the sort of misogyny it takes a mischievous female writer like Diablo Cody to muster. Jason Reitman directs Young Adult briskly and sparely, bringing it in at a crisp 90 minutes – the most uncomfortable 90 minutes that American comedy has provided in a while.

Next Week

Jonathan Romney watches David Cronenberg put Freud and Jung on the couch in A Dangerous Method