Blutsschwestern.

Three close friends discover a forgotten menstrual ritual in an old book. In an Italian cove near the hometown of Saint Maria Teresia Albrici, numerous female pilgrims are said to have menstruated together in the sea during the Middle Ages to experience a special bond. Without hesitation, the young women set off on a road trip to Italy. "And the whole world turns red, red, red," they sing together into the night.