Have you ever been waiting for someone you've met and missed for no reason? On Cloud Nine tells you about the story of love and the relationship between Tiew (Meen) and Mork (Rossy). Tiew promises to wait for Mork at Chiang Mai where they first met and missed. Mork comes back to Chiang Mai with different feelings for Tiew. Will Mork be back to Tiew to continue their unforgettable memories? Will they be on cloud nine?