William is convinced it is his fault that the world is coming to an end. On the planet's last day, he is faced with a dilemma; Should he spend his last hours with his family, who have chosen to celebrate his disabled sister's birthday, or should he meet up with his crush, who is impatiently waiting for him at the local beach?
I en øde landsby bygger en ensom knark et spejl af de materialer, han har til rådighed. Under det møjsommelige arbejde går manden uforvarende igennem spejlet og vikler sig dermed ind i en række uforudsigelige kædereaktioner – fra biljagter, slåskampe, orkaner over skovbrande til krige og en rumrejse – indtil han kommer ud på den anden side af spejlet, der viser sig at være fuldendt.