I first saw Fire in the Blood at work. It looked and sounded interesting, plus it wasn't listed as part of a series on Goodreads, so I added it to my to read shelf.
Then my mom got it for me for Christmas, so I eagerly started reading it...and realized it was book four in a series! That made me sad (it's very hard to find standalone fantasy books nowadays). I debated for a few days whether I should get a hold of the first three books or just read this one. In the end I decided to just read it. I regretted that decision for the first fifty pages or so. Most of that is back story, talking about events that happened earlier in the series. But once you get past the back story, Fire in the Blood gets quite good.
Fire in the Blood is about Farideh and Havilar, twin tiefling girls who were raised by their Dragonborn father, Mehen. Farideh is the Chosen of Asmodeus, a devil god; he grants her powers of the Hells which she doesn't want. The girls lost seven years of their lives due to a deal with a devil (I don't know all the details - I'm guessing this was an earlier book). They return to find the world has moved on without them. Havilar's noble lover, Brin, is engaged to Princess Raedra of Cormyr. Cormyr is fighting a war against Shadovar/Shade. Raedra's father, the crown prince, goes missing during the war. And Farideh sees a Shadovar agent in the princess's inner circle. Farideh ends up allied with the princess while Havilar and Brin go looking for the crown prince after everyone believes he is dead. And Havilar may be manifesting powers that mark her as a Chosen of Asmodeus, too. Mainly that she can summon imps who will do things for her - like give her a hellhound puppy so she can track the untrackable crown prince of Cormyr.
Oh yeah, and the ghost of the original Brimstone Angel is hanging around, trying to get a piece of her soul back. The only problem is that it's in either Farideh or Havilar. And she may have to kill them to get it back (once she is strong enough to do so).
There's also some stuff going on in the Hells. Lorcan, the devil who is supposed to be watching (and corrupting) Farideh, is getting embroiled in politics he doesn't want to care about. Plus his half sister may have stumbled on something the powers that be don't want getting out. I'm not going to lie: I really didn't care about this stuff. It was a lot more fun following Farideh, Havilar, and Raedra. They were dealing with kidnappers, political intrigue, war, magic, racism (Cormyr is not a friendly kingdom for tieflings!), love, heartbreak, and just so many fun and interesting things that it was so easy to be caught up in their story. They were all so relatable, that I really fell in love with them and their trials. I'm not in a hurry to read the earlier books, but I'll definitely be keeping an eye out for future books in the Brimstone Angels series!