Maddy, a 15-year old Thai girl, returns home during her boarding school summer holidays to live with her father, a self-absorbed emotionless man. In the forest not far from her home, an odd red light beckons her to enter. In searching for answers away from home, she ends up trapped by a shadowy figure who hides within a dark, mysterious tunnel she shares with millions of fireflies, insects that behave in an unnatural, almost possessed manner. Not only must she discover the key to her own escape, but also a way to break the dark pattern of entrapment, freeing both the mysterious dark figure and the fireflies themselves. And in doing so discover what is truly missing from her life, her fathers love.