何以笙箫默第五集World renowned journalist Sara Ogden is traversing the world in pursuit of carriers of a fatally dangerous "Stamp of Cain" in order to prevent seemingly unrelated events such as mass murders, turmoil, revolutions and chaos. She doesn't even suspect how close she is to the edge of the abyss, when in her search she ends up in Belarus to meet face to face with the one, whom she has been searching for her entire life.