In the spring of 1986 at the Chernobyl Nuclear Power Plant occurs an explosion. At the same time a girl called Mimi arrives in a small village in western Finland, and immediately fills fifteen-year-old Mariia’s life with radiating light. Twenty years later Mariia visits her childhood home and memories from the summer of her youth start rising to the surface, forcing Mariia to face her past.
The summer Mariia and Mimi got to spend together two decades ago was full of fierce joy but it ended tracigally. Years after the tragedy Mariia needs to remember the light, so that she can also accept the dark in her past and be able to forgive. Light light light is a film about first love and how blinding it can be and how long the shadows from it can grow.