A couple of days after I finished and I wonder if I can write a more coherent review (compared to my original review that only screams that I LOVE THIS).
One thing for sure, I rated Heart of Iron with 5* because I loved the hero, I loved the heroine, and I loved the additional player that made the arc more complicated. HOWEVER, I must say that My Lady Quicksilver would definitely be the better book, and my FAVORITE yet of the series -- and why I also gave it five stars.
What made this better? The battle of wits between Jasper and Rosalind (or when she was using her other personae, either Mercury or Mrs. Mayberry) was DELICIOUS. The sexual tension was through the roof -- I mean the "opening my buttons" scene alone??! GAH!! And through it all, it was a clever cat and mouse game. I thought Rosalind was a kick-ass heroine in a different way that Honoria or Lena. Rosalind was made an assassin but in here, she used her wit more than her ability to kill people. She went undercover -- but then she teased Jasper when she put on Mercury's costume. She's awesome.
And Jasper? Jasper won my heart too. I still loved my verwulfen Will but unlike Blade or Will, Jasper also preferred to use his brain rather than his blue blood strength. He still acted Alpha, but most of the times, as the Captain of the Nighthawks, Jasper went through clues, making connection between them. In a way, he was more like a detective rather than a rogue. And I always love smart guys too (brain over brawn people!).
There is a martyrdom scene that I usually disliked in a paranormal romance -- but I just couldn't feel that here. Probably because Jasper and Rosalind were just too perfect and the scene totally added the 'right' amount of angst.
I am totally IN LOVE with this series and the plot arc that Ms. McMaster are weaving. Totally cannot wait until book 4. Garrett and Perry!! Friends to lovers story!! It will be awesome!!