It's a pretty good thriller.
Kenzie is a black-ops assassin; growing up on the wrong side of the tracks, her choices as a teen left her picking between jail and the military. Now she is an adult, a crack shot with an appreciation of structure and the importance of orders, with no family or close ties. I.e., she is the ideal tool to mop up after failures of politics. Still, being a government assassin is a rough life, and when a particularly poorly planned mission goes belly-up, she is keen to cut her losses and leave the programme. She is sent on one final mission, to terminate a young woman studying in Mexico; even for her, the doubts grow too serious to ignore. Saving that young target (Cori), the two of them flee back to the United States in order to find the truth, dodging the agents sent to eliminate them along the way.
This book is action-packed and largely well-written; it struggles, however, with pacing. Several times the narrative abruptly halts for a lengthy info-dumps in the form of flashbacks. These most often appear to be a lazy attempt to justify some current choice of action. This is one symptom of a consistent problem, also seen in other transitions between scenes. Sometimes these happened so puzzlingly, or with such significant events happening "off screen", that I sometimes flicked back in the book thinking I had missed a significant chunk of text.
The mystery, by the way, is really a mystery. There are no clues or hints as to what the major conspiracy might be - although the situation is so cliche the reader will probably know the "twist" ending without needing any prompting. There are some attempts to tease some drama out of the situation with abrupt change-of-perspective scenes spread throughout the book, highlighting some villainous communication or potentially dangerous new kill order. Really though, they're not overly well done, and the conspiracy finally ends with the villains simply explaining the plot to the protagonists at the end of the novel.
The book also falls into a trap common to many thrillers, in that Cori is pretty useless - although I would like to emphasize that the author tried really hard in this instance to give her proper character development throughout. There are several times where her quick-thinking saves Kenzie's bacon, (although, again, some of the action was off-scree). I appreciated the drive to create a partnership of equals. Certain minor scenes also embraced the idea that Cori would learn awfully quickly if her life was in serious danger. But essentially Cori was so utterly outmatched by her partner's skill and experience that the author artificially hamstrung Kenzie by giving her a persistent wound - fair enough, but aggravating on many levels.
Honestly, it's pretty good -it was just the technical problems detailed in the first paragraph that dropped it a star. As it is, it gets three.