Like its predecessor, Heaven's Fire is a 5 stars, without question. I loved both Falcon's Fire and Heaven's Fire so much, that I can't even really separate them and think of them as two different books.
My Review for Falcon's Fire: http://www.goodreads.com/review/show/168207580
In Heaven's Fire, we get to hear Rainulf's story. Rainulf is the elder half-brother of the heroine in the first book. He is a brilliant scholar, teacher, and former soldier of the Crusades. He is also a Priest whose faith has been badly shaken, and he questions the validity of the Church and of God (as I stated in my review of the first one, these are most definitely NOT inspirational books, but they do have a lot of religious themes as the Church was a significant institution during the time period that these stories take place).
At the beginning of the book he finds out that the Church has released him from his Priesthood. He is teaching at a new school in Oxford, which Rainulf believes has the potential to be a great university one day (teehee). The Bishop also has set his sights on Rainulf to be the Chancellor of Oxford, which is a post he desperately craves. He was a celibate Priest for eleven years, and although he has been recently released from his vows, he still intends to remain celibate so as to be awarded the prestigious post of Chancellor.
Constance of Cuxham has spent the majority of her young life trading her body for protection... specifically protection from Sir Roger Foliot, a sadistically evil knight who brutalizes all who are under him, especially women. And Sir Roger is obsessed with Constance. She has managed to stay protected from his wrath because she married an old man when she was quite young (and Sir Roger fears the fires of hell, and would not violate another man's wife). Then after she is widowed she takes up with Father Osred, an elderly priest, and lives as his mistress and housekeeper in exchange for his protection from Sir Roger. She is tired of being used, and longs for freedom. Years later, when a small pox epidemic kills the old Priest, Constance is once again left open for Sir Roger's taking.
Rainulf is asked to go into Cuxham to deliver Last Rites to those who've been stricken with small pox, as Rainulf has had the disease and is therefore immune. He finds Constance digging a grave for Father Osred. She is also stricken with fever, and Rainulf sees her through the night. He feels an instant connection to the young widow, and also notices that she has a great talent for copying text and illuminating. After he leaves Cuxham, however, Rainulf receives news that Constance has died, and he feels a profound sense of loss that he cannot explain.
Constance hasn't died. She has faked her own death, and has escaped Cuxham. She goes into hiding from Sir Roger, and makes her way to Oxford to seek out the young priest who helped her. She now calls herself Corliss, and is very convincingly disguised as a boy. Rainulf, relieved to see her alive, finds himself unable to let her go. He takes her into his home to protect her, but if she is discovered to be a woman by the people of Oxford, Rainfulf's reputation would be ruined, and Constance would leave herself open to being kidnapped by the man Sir Roger has sent to find her.
As they spend more time together, Constance and Rainulf are drawn to one another forcefully and undeniably. Their attraction and growing love is so powerful, that the reader can actually feel the distress and the sheer emotion flowing from these two characters. Patricia Ryan seems to love writing stories where the characters desperately try to resist one another for a long time, creating a tension so thick that by the time they give in and release the tension, it's a veritable explosion. And this book was the most explosive so far.
By the time these two characters give into their passion, they are completely in love and have longed for one another so much, that their coming together is one of the most intense I've ever read in any romance novel. Their first love scene is one that I may go back a reread several times. Seriously, seriously hot. Not only was it hot, but the reader also had the emotional involvement as well. These are two characters who have essentially given up on falling in love, and are surprised to find in one another everything they have ever wanted. Once they figure out how they feel about one another, the expression of that love is so beautiful and moving.
In addition, reading about Rainulf's personal journey towards finding himself and what he wants was interesting to read. He is a fabulous teacher, and although Corliss/Constance can see that it is his passion, Rainulf seems blind to this notion. She helps him find himself, which only adds to the genuineness of their feelings for one another.
This could be read as a standalone, but both of the Fairfax books were so good, that I would recommend reading them together and in order.
What are you waiting for? Just read it! You won't regret it!