Night Shadow is the first in this series that I have read, although there are clearly several previous books in the series. I'm not sure if it is the author's writing style or if the previous books contained information relevant to this one that wasn't repeated, but at times I was very confused as to what was happening. The heroine, Lexi Stone, is a T-FLAC operative (I am still not sure what T-FLAC is or what it stands for) on her first mission when things start to go wrong. She's teamed up with a wizard with the confusingly similar name Alex Stone and desperate to prove that she can be a good operative, despite having previously worked in a back-room office function. When various terrorists threaten groups of people spread widely around the globe, and the terrorists all look like a younger Alex Stone, it's clear there's something very strange going on.

The action is fast in this story - Lexi and Alex travel from Taiwan to Russia to Los Alamos to Berlin in the blink of an eye. They follow a trail which leads them to suspect an army of clones is being created, but I was never entirely sure how they made the leaps of imagination that they did. The romance aspect of the story is perfunctory and rather uninspiring, and the complexity of the plot, where I always felt I didn't have enough information (and neither did the characters) to make the deductions that were made, resulted in the book being rather unsatisfactory. Some heroes and heroines of previous books are brought in toward the end, but they don't add much overall to the story, and I felt my attention wandering.