Every five years, 30,000 people gather on the same stage in the small country of Estonia to join voices at Laulupidu, the National Song Festival, to become the largest choir in the world. More than a song festival, Laulupidu is an Estonian miracle that at least twice in history gave freedom to that country. TO BREATHE AS ONE explores the beauty and meaning of the choral festival through the eyes of the young members of the San Francisco-based Piedmont East Bay Children's Choir, one of the few American choirs invited to participate. Learning complex songs - all in Estonian - the youngsters prepare for months and then set off to join the many thousands from around the world who gather every five years in Tallinn. Forming cross-cultural friendships that span the oceans, there they discover the unique role that music has played for Estonians for over 150 years, as an integral force in maintaining strength and identity for a people who have faced cultural genocide - more than once. From the filmmakers of the acclaimed, "The Singing Revolution", the film reveals that for Estonians singing is not just a means of cultural expression, but a defining part of their identity.