Invisible Murder    by Lene Kaaberbol & Agnete Friis Order:  USA  Can Soho, 2012 (2012) Hardcover, CD, e-Book      Reviewed by Hilary Williamson Invisible Murder follows The Boy in the Suitcase in an unusual yet gripping series, written by Lene Kaaberbol and Agnete Friis, and starring driven Danish Red Cross nurse Nina Borg. Nina is married to Morten whose job often takes him out of town. They have two children, small Anton and teen Ida, who is perpetually hostile to her mother. Though the series is set mainly in Copenhagen, the action ranges across Europe. Nina works under the radar with refugees and illegal immigrants, and these activities keep getting her into trouble. After events in the first episode, Nina's husband Morten extracted a promise from her to do no underground work for the Network in his absence - of course readers know she will be impelled to break her word. Invisible Murder opens on two Roma (gypsy) boys in northern Hungary, exploring what was once a Soviet military hospital. Tamas gets into the sealed basement, finds something valuable, and brings it back to their community. Next the authors introduce an elderly man, trying to leave his finances in good order on behalf of his much younger wife - their bizarre role in events only becomes clear late in the story. We see Nina and her boss Magnus trying to deal with a tragic situation which the system only seems to worsen. And we meet half-Roma Sandor, trying to fit in. His life swiftly goes downhill after his half-brother Tamas shows up and uses his computer to search online for sales opportunities for his find. Finally, the authors show intelligence operatives performing a drill. The call that makes Nine break her promise is about a Roma from Hungary with severe food poisoning - many others quickly come down with the same illness, which is eventually diagnosed as radiation poisoning. Kicked out of university, Sandor heads home, where he is forced by family debts to travel to Denmark in search of his errant brother. Naturally, his path crosses Nina's, which is when the action and violence escalates. I found Invisible Murder even better than The Boy in the Suitcase. As before Lene Kaaberbol and Agnete Friis deliver a convoluted thriller, and solutions to their puzzles are never obvious ones. They're very hard on their poor misguided heroine - I am already anxious about what they plan to put her through next time around! Note: Opinions expressed in reviews and articles on this site are those of the author(s) and not necessarily those of BookLoons. Find more Mystery books on our Shelves or in our book Reviews