The story follows a 16-year-old Icelandic boy, Ari, who lives with his mother in Reykjavík. She has to leave the country for a new job, sending him back to the small town of his youth. There he finds his old friend, suddenly a young woman with a tricky romantic relationship; and his father has become a victim of the financial crisis.

When the light breaks on a long summer's day in Iceland. From one sunset to another, Una, a young art student, encounters love, friendship, sorrow and beauty.

Through 56 independent scenes, Echo draws a portrait, both biting and tender, of modern day Iceland during the often turbulent but also exciting time of the Christmas holidays.