After making a splash with his directorial debut “Hereditary,” writer/director Ari Aster returns with another slice of horror in the haunting slow-burn “Midsommar.”

Aster’s follow-up is another daring entry into the horror genre – a film that disturbs its audience and will stay with you long after you leave the theater. It doesn’t quite have the same psychological impact as Aster’s previous work, but it is still quite effective.

“Midsommar” follows Dani (Florence Pugh) and Christian (Jack Reynor), a young couple who appear to be on the outs. Just as Christian is ready to end the relationship, Dani’s family suffers an unspeakable tragedy – with Christian being the emotional support Dani desperately needs.

Six months later the couple are still together and Christian is about to go with his three friends (Will Poulter, Vilhelm Blomgren, and William Jackson Harper) to Sweden for a festival in a small community that occurs every 90 years. 

Sensing Dani still doesn’t want to be alone, Christian invites her to come along. The trip starts out well enough, until the couple start to suspect that this sunny paradise isn’t all it appears to be.

Aster has crafted one of the most visually impressive horror films in recent memory, using his camera lens to bring to live the beautiful color palette of the location in stunning fashion. But the cheering visuals serve as a canvas for something sinister boiling under the surface – a tension that is amped up with some impressively hallucinatory special effects.

Like “Hereditary” the horror comes from some common places deep in one’s psyche – a film that explores family and grief in an honest manner, albeit in a circumstance that is anything but normal.

Pugh and Reynor make it work with two solid performances, while Poulter provides some needed comic relief to ease the tension in the 140 minute film.

To Aster’s credit he juggles the lengthy running time quite well – allowing his story time to breathe and building to a horrific second act that rewards its audience’s patience.

Aster’s film does linger a tick longer than necessary, but it’s a small gripe for an experience that is most memorable – and completely unsettling. 

Starring: Florence Pugh, Jack Reynor

Directed by: Ari Aster

Rating: R

Playing at: Regal Bowling Green Stadium 12, Regal Greenwood Mall Stadium 10, Highland Cinemas (Glasgow)

Grade: B