Season 1 of The Last Room No.6 premiered on July 20, 2021.

Piang, an ordinary girl, who was born with a sixth sense that makes her able to see any spirit, gets an urgent mission to take care of her aunt’s mansion. However, something scares her, and she faints before even reaching the room. She thinks she saw a spirit, but actually, it was just a ghost show her ex-boyfriend, Guy, who was filming a woman who secretly fell for him from room no. 6, Belle, starred as the ghost. After Guy learns that Piang has such a talent, he then asks her to help him make the show and sell it to a TV channel. Mysterious things happen when Guy edits the files and finds out that Belle completely disappeared from the scene. He asks her to re-shoot and Belle is more than happy to help; that's the first time he finds he cannot see Belle in the mirror!