The fine line between ‘belief’ and ‘truth’

Delusion, an original mystery series, is a mystery-led investigation set in northeastern Thailand, where the quiet devastation of dementia collides with the chilling local folklore of "Phii Pong". The series streams on Netflix on Sept 24.

Delusion plunges viewers into a chilling mystery set in the quiet district of Chiang Khan, Loei province. A child's disappearance reawakens something the town has spent over a decade trying to forget and bury.

As fear takes hold, the old legend of "Phii Pong" resurfaces and as the town hunts for someone to blame, the suspicion settles on "Narong" (Surasak "Nu" Chaiyaat), an elderly man whose worsening dementia makes him impossible to defend and impossible to trust — even by his own family.

This forces his daughter, "Wan" (Natapohn "Taew" Phornprapha), a provincial high school teacher, to stand up and fight a battle against the town’s rumour and to prove that her father is only a sick man who needs care, not the monster the town has decided he is. But every answer she uncovers only raises more questions and the closer she gets to the truth, the less she recognises the people closest to her, the ones she calls family.

Beyond its gripping narrative, Delusion is anchored by a cast taking on some of the most challenging roles of their acting careers. Taew said that the character deeply resonates with her real life, particularly the struggles of a generation trying to build their own lives while carrying the anxiety of caring for aging parents.

The personal connection fuelled her dedication to portraying Wan as authentically as possible. Defining the show's core appeal, she explained: "For me, it’s about 'deception'. It makes the audience question what kind of series they are actually watching — is it a mystery, an investigative thriller, or a profound family drama? But there’s something hidden within that ultimately makes you realise why the story had to be told this way."

Jespipat "Jes" Tilapornputt plays "Pete", a detective transferred from Bangkok, and is someone who believes only in what evidence can prove and his own eyes can see — not superstition, not rumour and certainly not fear.

Jes revealed the intense preparation behind his role: "I had to study the script heavily because the plot is highly complex with a lot of details. I attended several workshops and spoke with real police officers, both from crime and investigation units and the general detective unit, in order to fully understand the differences between them. Even though this is not my first time playing a police officer in my acting career, it was the first time that I truly understood the differences between investigative and interrogative police duties."

Vachiravit "August" Paisarnkulwong takes on the role of "Wat", the family's beloved youngest son. He admitted to feeling immense pressure stepping into the part: "Working alongside so many top-notch, experienced actors meant I had to do more homework than ever before. I had to dig deep into Wat's background to justify his actions in every single scene. I also went through numerous solo and group workshops to truly understand the character on a deeper level before filming, which really helped me in the most effective ways."

The intense narrative is further elevated by a powerhouse supporting cast, including Sirani "Tom" Yankittikan, Suttawat Settakorn, Boombim Samtone and rising child star Norraphat "Tham" Nakadumrongchai, who together make this dark mystery complete and unmissable.

What sets Delusion apart from typical mystery series is its artful play with ambiguity. Viewers are left stranded between every possibility, unable to guess the true root of the horror: Is it the supernatural folklore of the Phii Pong? The tragic delusions and memory loss caused by a brain disease like dementia? Or a dark, twisted secret intentionally buried by the family?

Director and co-writer Chayan Laoyodtrakool explained the vision behind this unique blend: "The core of this story is family dynamics, heavily layered with mystery, crime and investigation, and family drama, which amplifies the emotional weight of the series far beyond expectations. I believe that by the end, viewers will be left with a deeper understanding of human nature; one that's closer to them than they might think. This series invites everyone to sit with their own feelings, guided by the story's central question: 'When the person you love becomes someone else, can you still trust what you see?’"

Prepare for Delusion, which streams on Sept 24 on Netflix.