The film cuts back and forth in time, showing Martha's life with sister Lucy (Sarah Paulson) and her husband Ted (Hugh Dancy), and the events leading up to her escape from an isolated Catskills farm community. Lucy and Martha haven't spoken for two years, but the former's good nature and desire to have a child trigger her maternal instincts and Martha is welcomed into her Connecticut home. The younger sister's behaviour is viewed as eccentric at first as she adjusts to life outside of her "family", yet her mental tailspin picks up speed when she gets into bed with Lucy and Ted while they're having sex and later has a meltdown at a party they're hosting. Martha unfolds through the eyes of its titular character but she's an unreliable guide, her psychological fragility and increasing paranoia mean that the past and present overlap, something Durkin illustrates visually with some clever editing.
Olsen's performance is made all the more remarkable by the fact that Martha is so emotionally closed-off and distant. A lost soul, she appears to find salvation with the creepy and charismatic cult leader Patrick (John Hawkes), but a violent initiation ritual at his hands sets in motion her unravelling. Martha Marcy May Marlene is held back by cool detachment and self-conscious restraint from Durkin - it's a thriller completely lacking in thrills. While it could be argued that fellow Cannes entrant We Need to Talk About Kevin is horror without the visceral scares, it's so completely engrossing from the off that by the end you're left completely stunned. Martha falls just short of making a similar impact, but the hugely impressive turn from Olsen makes it worth a look.
> Trailer: Martha Marcy May Marlene
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