The heroes of the "Call of Blood" project grew up in single-parent families and were raised in orphanages. But they did not lose hope of finding answers to the damned questions about the mystery of their birth. Participants in "Call of Blood" go in search of the people closest to them – their mothers or fathers. They are ready to travel kilometers for the sake of their goal. This journey is the main thing in their lives. Because there is nothing stronger than the call of blood.