This was silly. And at times straight-up ridiculous. But there were a few moments that made me go "aw" or made me smile, and for that it gets 2 stars.
The romance itself between Kilian and Donovan is rushed and unbelievable and without any spark whatsoever. It's like they both were just like "Hey, so you and I are alone in this here train car together, and we're both apparently gay and horny... that must mean we're meant to make out! But wait, that's not respectful enough of you, because even though we only just met and have barely spoken I know you deserve better. So it must mean we're meant to fall in love!"
So, yeah. Silly. And ridiculous. But I soldiered on because for some reason I was in the mood for a shifter story. The shifter lore itself was also ridiculous and never even attempted to be explained well. All we know is that it's a formula Sam stole from some American. Never how it was developed or how it can turn different people into different animals. Or even turn someone into an animal that doesn't actually exist...
Okay, wow, so lots of negatives there. I still decided to give this two stars instead of only one because there were a few scenes (mostly the fight scenes, where I got to see cool shifters doing their thing) that intrigued me enough to overlook the ridiculousness of the rest of the story.
Not one I'll likely read again, and not one I'd really recommend. Having being a shifter imposed on people through a formula is an intriguing idea, however, and it's one I'd like to see explored more in-depth.