4.5 stars!! The Bellas' joint review: 
 Cathy: I really liked this story about Jackson and Serenity! I felt sympathy for Serenity because of the situation she was forced into by Hogan, at the same time I was mad at her for doing what she was to the MC. I really loved Jackson. He's kind and helpful underneath the rough exterior. He really wants to help Serenity sort her shit out. It doesn't 
 hurt that that he is hot as hell and the sex is great. Knights' Sinner is a great, quick read. 
 Ellen: Once again, Bella delivers a super-hot, sexy story with characters you can sympathize with. I loved Serenity and the chemistry between Jackson and her is amazing. There are some super-steamy scenes between them, I loved Jackson because he is a little older and really knows what he wants. The age difference between Jackson and Serenity keeps things interesting. The story has just enough tension and drama to keep this a page-turner, there is some violence but the sex is HOT HOT HOT. And although I am sad that this is the last book in this series, Muff will be getting a novella! I can only hope it will be as hot as the MC Sinners' books!