Have you ever been waiting for someone you met and missed for no reason? On Cloud Nine tells you the love story and relationship between Tiew (Meen) and Mork (Rossy). Tiew promises to wait for Mork in Chiang Mai, where he first met and got lost. Mork returns to Chiang Mai with mixed feelings for Tiew. Will Mork return to Tiew to carry on his unforgettable memories? Will they be on cloud nine?