Immortality is a sequel to Anatomy. Sadly for me this book did not live up to the first one for me. 

Immortality tells the story of our dear Hazel who is a physician (not a loud for a woman during this time), and she is able to save people that others have written off. This is what leads her to be in hot water and gets her arrested, but due to her healing abilities, she is requested to become the physician for Princess Charlotte as nobody else has been able to heal her from a mystery illness. Once at the palace she quickly catches on that things are not what they seem, but she does her best and starts coming up with ways to heal the princess. In her free time she gets to spend time with the other Royal physician and even gets to meet a secret society who requests her as they think she is one of them. Little do they know that she isn't the one who took the Everlife eliquir in the first book, and instead gave it to her beloved Jack. 
Between this secret society, still looking for Jack who she has not seen since she saved him, and trying to save the Princess Hazel is a little bit busy in this one. 

Overall this book was okay to me. It felt like at times it was trying to hit a lot of tropes and catch on to the hype with Queen Charlotte and Bridgerton that was going on around the time it was published. Maybe thats just me reading too much into it though. I still like Hazel as a character and how she is able to keep her morals and convictions despite those around her trying to get her to break and do terrible things. However I also felt like this book was just trying to do too much, and if it had just focused on the secret society and the princess it would have been better in my opinion. 

I think if you loved the first book in this duology, you probably won't love this one as much.