Even the film's stars were traumatised by the final cut, with actor Will Poulter telling Vulture: "I was so f***ed up after watching it that I didn't sleep. It's maybe the most aggressive reaction I've ever had to a film."
Likewise, viewers have reported extreme reactions to the horror since it opened in cinemas, with many saying they were unable to sleep.
The film follows the story of an American couple on the rocks who decide to join a group of friends on a trip to a midsummer festival in an isolated Swedish village.
Set during the summer solstice, the film takes a sinister turn as the villagers involve the visitors in increasingly disturbing rituals.
The film's official trailer reveals graphic glimpses of disembowelment and violence, with all the horror carried out in broad daylight.
Meanwhile, some fans found the film to be a deeply moving experience away from the horror.
Aster made his directorial feature debut with Hereditary last year, which earned widespread infamy as one of the scariest films ever released.
Midsommar will be in New Zealand cinemas from August 8.
