Mist is a mix of urban fantasy and Norse mythology. For me, the combination -- at least as presented here -- just doesn't work. 
 After a promising prologue set in a snowy wasteland along a Norwegian border during World War II, the action jumps to modern day San Francisco -- and the story falls apart from there. 
 Main character Mist is a Valkyrie, who after the final great battle of the gods is left to wander Earth protecting one of Odin's treasures. She's beautiful (of course!), can kick butt, and is burdened with a tremendous sense of both guilt and responsibility. After keeping a low profile for decades, Mist starts noticing odd signs and portents, as well as bizarrely cold weather, and soon discovers that Midgard (Earth) is under assault by frost giants, the Jotunar. Perhaps the old world isn't quite as dead as Mist believed, but there's no time to sit and ponder. Attacks on Mist and her associates begin to multiply, and before long Mist realizes that Midgard may well become little more than the next battleground for a mighty confrontation of the Aesir, the Norse pantheon of gods and goddesses. 
 Mist lives in San Francisco, training with swords and working on her fighting skills, until all hell breaks loose when the frost giant Hrimgrimir and an unexpected elf show up in her world. From this point forward, Mist spends most of her time racing around the city, getting into fights, assembling a team of allies, and figuring out who she can count on -- and which people are not as trustworthy as they seem. There's tons of action, confrontations, emotional scenes of betrayal and alliances... but I don't know, it was incredibly difficult to follow. 
 So why didn't I enjoy this book? Several obvious problems, for starters. 
 Problem 1: The first several chapters read like one gigantic info-dump. The exposition is jam-packed with names and details, and if you're not already familiar with Odin, Freya, Valkyries, Einherjar, Aesir, Ragnarok -- and on and on -- you may find your eyes glazing over, as mine did. 
 Problem 2: So what exactly are Mist's powers? What are the rules? She can guard the Treasures, but not use them? She can be hurt, but she can heal, so is she immortal? She's strong, but can be defeated in battle -- can she be killed? She can use runes, and apparently has access to all sorts of magic, but she's less powerful than some and more powerful than others. And what about the rest of the Norse mythological characters who show up? Same questions apply, and not all answers are clear. In order for me to get behind Mist as the hero of the story and really care about her struggles and her fate, I have to feel that I understand her... and I don't. Magical worlds are great, but it's important to get a sense of the rules of the magic involved if the world is to be convincing. It was practically impossible to tell what each character's limits and powers are, so that their stories seemed a bit arbitrary to me, changing or discovering new magical talents as the need arose in the story. 
 Problem 3: One thing that drove (ha! you'll see) me batty was that the author seemed to be trying to prove that she really knows San Francisco by constantly providing a turn-by-turn set of directions every time Mist had to get from place A to place B: 
 Without really thinking about her destination, Mist turned north on Third Street and left on Sixteenth Street toward Golden Gate Park on the other side of the city... She parked along Lincoln Way, got out of the car, and entered the park from Nineteenth Avenue. 
 And a few chapters later: 
 She pressed the Volvo to its limits, reaching eighty as the car crossed over Highway 101. She flew along the Embarcadero Freeway and raced down the Twentieth Street exit ramp. She screeched right on Twentieth, crossed Third on a yellow light, and made a hard right on Illinois. 
 Thanks, but I have a GPS for that. 
 Mist is supposedly the first book in a series, and so it doesn't end with a definitive conclusion. Instead, the final section of the book mostly deals with team-building, as Mist assembles allies to join her in the coming fight against Loki and whatever array of baddies will join him in the fight to take over Midgard. 
 Overall, the book felt like all plot with no strong underpinnings of character or context. I generally enjoy urban fantasy, but didn't feel that I had enough to go on with Mist. The characters seemed too vaguely defined, and therefore unknowable. Interestingly, Loki was the only character I felt I could get a handle on; he's a trickster, he's scheming and manipulative, and that's something that remains consistent throughout the book. Without the ability to really understand Mist herself or her allies, it was hard to invest in the story. 
 I'm sure that there are readers who will have a very different opinion of Mist than I did. People already conversant with the names and terminology pertaining to Norse mythology may not mind the unwieldy exposition and info-dumping -- and may not need to refer back to Wikipedia and D'Aulaires' Book of Norse Myths as often as I did. Plus, fans of urban fantasy may enjoy the many fight scenes and chase scenes that compose much of the plot. 
 For me, the truth is that I had to struggle to finish reading Mist, and if not for the fact that I'd received this as a review copy, I might have walked away after the first few chapters. I stuck with it to see if it would get any better -- sadly, I never felt that the story really built into anything I could connect with or invest in, and by the end I was just reading it for the sake of finishing. 
 Disclaimer: Review copy courtesy of Macmillan-Tor/Forge via NetGalley. I received this review copy in exchange for an honest review.