Angel's Flight (The Phantom Saga #4)

Who is a Phantom without his opera? What is an Angel without music? Erik and Christine have fled Paris to pursue a new life, but their dark past is difficult to escape. Pursued across Europe by mysterious adversaries intent on taking all they have, the bonds of their love are tested. As husband and wife, they must confront their scars and demons, while as lovers, they delve into their most dangerous desires.
Meanwhile, at the opera house the phantom left behind, a new mystery evolves as a new figure in a mask begins to wreak havoc on the patrons. Meg Giry, a curious young dancer who has only known the ghost as a legend, takes on a search for answers that leads her to the door of the infamous "Persian" and perils that will change her forever.