New York, 1955. It's become dangerous in the city. The mafia is attempting to capture power. But lately, a brand new force appeared. A far more terrible force. Over the previous few days, five mafia chiefs have disappeared in mysterious circumstances. A butterfly plus a strange liquid were found at the scenes of the disappearances. But this isn't what frightened the citizens... Kids began to vanish in the city. Before they evaporated, all of them brought just the same butterflies. This induced detectives and journalists to start their investigations.