In the anticipated second book in the Black Spiral Trilogy, mere fragments of relationships and lives remain. The M-fever survivors are few, and they are either incapacitated or loathe each other. A top-secret mission to Berlin to delve into the misdoings of the Spirale Forschung (Spiral Research) organisation has been only partially successful and very costly. The Javier virus poses an even more potent threat than its predecessor, and in the wrong hands could be catastrophic.

Survivor and stubborn adventurer Violet Black is increasingly out of her depth. Her boyfriend has met a violent demise and she is now teamed up with his slayer, Phoenix. Whether Phoenix had any other options she considers beside the point. Under the guise of non-existent, mandatory contracts, they are further exploited.

In a frightening world of shapeshifting, blocking and reading of others' thought-streams, and highly sophisticated VirtReal simulation, Violet and other individuals must fight not only for their lives but for all those about to be experimented upon, reprogrammed and wiped out by the deeply sinister Spiral Foundation, with its claws forever reaching outwards.

Whereas Violet Black, the first book in the series, by necessity set up the action and introduced heroes and foes, in Black Wolf Merriman has taken every opportunity to flesh out the story substantially. She clearly enjoys the malevolent world of her creation and the individuals who strive through it. Showcasing a vivid imagination, Merriman allows her main characters to become fully developed as they struggle both within themselves and with their dire circumstances. With relatable personalities that can quickly turn defensive, Violet and Phoenix gain the reader's attention and empathy. Violet, for instance, struggles with grief, which sometimes manifests as sarcasm. We spur them on as they adventure across the vast drylands of the Northern Territory. From a Berlin winter, our characters are now submersed in roaring Outback heat.

Merriman has also embellished the romance theme. This developing relationship and its in-depth portrayal may be unappealing to an adult reader but will no doubt be a major drawcard for teenagers. The tensions between these two drive on the action, sometimes acrimoniously, and other times as a team. The romance is given almost as much prominence as the quest itself.

Violet and Phoenix have at least triple layers accumulating within themselves: their birth identities, their pseudonyms and characters when fighting the hostile forces, and their animal forms. This is another expansion from the more straightforward book one. To complicate matters further, the name "Black Wolf" merges together aspects of both protagonists' identities.

Black Wolf could have become too complex, but Merriman holds it all together with her carefully mapped timelines, believable characters and a firm grasp of the dystopian dramatics. The narrative, like in book one, continues with first person accounts, allowing our characters to interpret their own experiences. This is just as well for all around them swirls destruction, falsities and "corkscrew truth," where villains wear blocking devices to stop their intentions being read, use "pods" for experimentation and threaten with NET scans and electrotherapy.

With more detailed coverage of characters from book one, a deepening plot and a startling new setting, Black Wolf is engrossing. While it could be read as a standalone novel, it would be more sensible to read in order, especially to understand the science fiction elements. Despite the insidious machinations, Merriman leaves an overarching impression of fun. While Violet and Phoenix are defending their own lives, inversely they also seem to be enjoying their escapades. We will wait to see, in the forthcoming Black Spiral, if indeed the Foundation can possibly be stopped in its tracks.

Reviewed by Jessie Neilson