Cassandra Clare, author of the best-selling The Mortal Instruments trilogy, knows she is onto a good thing; she has now made the clever move of penning a prequel series to the three novels.
The mixture of romance, Gothic horror and magic is going to be the same again, but on this occasion the time and place has changed from contemporary New York to late 19th century London.
The good thing about prequels is that fans don't have to wait to move on to the rest of the story if they are hooked by what they have read.
Clare's new Infernal Devices series is going to be a trio of stand-alone novels that will lead nicely onto her well-established The Mortal Instruments saga.
For Clare novices, Clockwork Angel is a thrill-a-minute, self-contained novel that will certainly have new readers panting for more of the same.
There is a lot going on in the book, with Clare hardly giving the reader time to breathe and take it all in. Setting it in Victorian London allows for the book to be packed to bursting with thrills, romance, Gothic atmosphere and more evil creatures than you can shoot a silver bullet at - or drive a stake into.
Yet Clare is totally in command of her setting, characters and plot and just stops short of over-egging the pudding.
On the death of her aunt, 16-year-old New Yorker Tessa Gray crosses the Atlantic to London to live with her brother. She has hardly stepped off the boat before a pair of sinister old women, called the Dark Sisters kidnap her. Tessa thinks the women are taking her to her brother's home, but she is dead wrong.
The Dark Sisters know something about Tessa that she does not know herself. The young American teen has the latent power to become a Shape Shifter, and the old women have been instructed to train her to develop and release her potential.
The Sisters keep Tessa captive while teaching her to exploit her ability to change into other people, dead or alive. Mrs Dark and Mrs Black work for the Magister, the leader of the Downworlders, ancient vampires, werewolves and warlocks who stalk the shadowy streets of Victorian London.
Tessa discovers that the Dark Sisters intend her to marry the Magister.
Tessa is rescued from the clutches of the Dark Sisters by a mysterious young man who reveals himself to be one of the Shadowhunters, a secretive breed of half-human half-angel Londoners intent on destroying the powers of the Downworlders.
The stage is set for a classic showdown between the forces of good and evil -with just a splash of Gothic romance thrown in for good measure.
Clockwork Angel is a dense, imaginative and persuasive piece of teen Gothic fiction that leaves the coffin lid wide open for the next adventure. Believable? Of course not! But it is highly addictive and fun.