Forbidden Fires is the hottest of the series thus far. Delia and Colin are working together to solve an arson case. But they also have a past together and there is a lot of unresolved feelings and attraction. The investigation leads them to a BDSM B&B, posing undercover as a married couple. During the investigation, Delia's desire to be a submissive comes to the forefront. Colin is shocked and turned on but is not sure that he can be the Dom that Delia needs.Forbidden Fires is my favorite of the series so far. It is so hot and sexy. The attraction between Colin and Delia is evident from page one. Once Colin and Delia went undercover at Bondage and Breakfast, I was immersed in the BDSM training with Master Gabriel. We've met Gabe in previous books and he's still an enigma. I hope that Gabe gets his own book because I can't wait to learn more about him and meet the woman that brings him to his knees.The BDSM training brings forward feelings that Colin and Delia still have for each other. I was so drawn to their relationship and the smoking hot sex scenes that I almost forgot that there was a mystery that needed to be solved. To be honest, I wasn't too interested in finding out who was behind the arsons. Does that make me a bad person? Haha!I enjoyed reading Forbidden Fires. Even though it's part of a series, it can easily be read as a stand alone. If you want to read a sexy, steamy read with a little mystery thrown into the mix, then I highly recommend this book.