The protagonists find many trails, explore abandoned mansions and gardens, get anonymous papers, and conduct interviews.

One day she takes him to the cemetery of Sarriá where she tells him about the peculiar "lady in black" that comes here on the last Sunday of every month at ten o’clock in the morning.

"He’d turned into a hellish creature, stinking of the rotten flesh with which he had rebuilt himself..."[4] Using the essence of Teufel, –the black butterfly that habits the sewage system –he develops a serum that sustains his life.

He has resurrected like the black butterfly from the sewages that "feeds on its young, and when it buries itself to die, it takes with it one of its larvae, which it devours when it comes back to life".

[5] Marina Blau and Oscar Drai penetrate this history hidden between suburbs and narrow streets of the dark and gloomy city.

The Guardian: 'Marina is one of those books that are meant to be devoured in one sitting; feasted upon quickly, as it will truly curb any hunger you might have had for a good read.

Unlikely discoveries in mysterious, half-ruined mansions alternate with spine-tingling action sequences to create a grotesquerie that will delight horror fans.