Tana lives in a world where walled cities called Coldtowns exist. In them, quarantined monsters and humans mingle in a decadently bloody mix of predator and prey. The only problem is, once you pass through Coldtown’s gates, you can never leave. One morning, after a perfectly ordinary party, Tana wakes up surrounded by corpses. The only other survivors of this massacre are her exasperatingly endearing ex-boyfriend, infected and on the edge, and a mysterious boy burdened with a terrible secret. Shaken and determined, Tana enters a race against the clock to save the three of them the only way she knows how: by going straight to the wicked, opulent heart of Coldtown itself.The Coldest Girl in Coldtown is dark, dangerous and fast-paced, held together by flawed and deadly characters. Black brings new life to vampires in this incarnation of the creature. Along with the vampires, Black gives readers Tana, a reluctant heroine with secrets of her own and a way of making the wrong decision that only serves to get her deeper and deeper into the heart of Coldtown.In the beginning, Tana is by no means the hero of the book. She just happens to be the only survivor of a vampire attack on a house party, she just happens into the room with her infected ex-boyfriend and a mysterious (and possibly insane) vampire. She just happens into everything that follows, going along with the flow, but she has her reasons. And she doesn't run from the situation, she feels the need to follow it, to keep going, and so she goes with them into Coldtown. The dark secret in her past complicates things, fill her with thoughts of not belonging, and this pushes her to continue the journey through the gates.The reason Tana follows along and continues deeper and deeper into a complicated situation is because she makes mistakes. She doesn't always put her trust in the right person, she isn't always the smartest girl around, but she actively wants to fix those mistakes. No whining, no passing it off on someone else, someone stronger or deadlier. Tana has the ability to take charge, to make the hard choices, and she does it.The vampires in this book are shown in a darker light, the way a creature known in horror and genre circles should be shown. Vampires are deadly, brutal, an infection, a menace to be locked away and kept from killing the human population. There are those characters who do glamourize them, who want to join them, who see beauty in life after death and living in a cold popular cage, but they are the minority. For most, they feel safe with the existence of the Coldtowns, knowing the vampires are locked away and can't escape. Unless someone lets them out, of course.As exciting and blood-stained as this book is, there was something that bothered me. Nothing plot-wise or character-wise, but instead the timeline of the book. I felt the flashback chapters, those on Tana's past, on the vampire's past, interrupted the story that was currently taking place. While each chapter is related to how Tana ended up in Coldtown, it stopped the flow of the story for me.Vampire characters in YA are overused, but what Black does, by including Tana, by tweaking the modern world with the addition of the Coldtowns, is give readers something new. This book has a way of being both familiar and original. Dangerous consequences arise after each and every decision made in Coldtown, and every attempt to help or fix a problem is painfully difficult, but that doesn't stop Tana from trying to save everyone she can.