Summery 
 Gwen has a destiny to fulfill, but no one will tell her what it is. 
 She's only recently learned that she is the Ruby, the final member of the time-traveling Circle of Twelve, and since then nothing has been going right. She suspects the founder of the Circle, Count Saint-German, is up to something nefarious, but nobody will believe her. And she's just learned that her charming time-traveling partner, Gideon, has probably been using her all along. 
 Emerald Green is the stunning conclusion to Kerstin Gier's Ruby Red Trilogy, picking up where Sapphire Blue left off, reaching new heights of intrigue and romance as Gwen finally uncovers the secrets of the time-traveling society and learns her fate. 
 Rating 
 I gave this book a four stars because it was a good book just it didn't live up to the rest of the series which is a shame. I didn't feel fulfilled at the end of the trilogy which was annoying. There were questions and plot lines I still wondered about (view spoiler)[What the hell happened to the Philosophers stone (hide spoiler)] and some of the plot twists were predicable but it was still overall a decent book. I wanted some areas to be resolved and I wondered if someone was touching either Gwen or Gideon would they be brought to the future with the pair cause they could take and bring things so does the same apply to people? 
 I was confused about (view spoiler)[Gwen saving the life of James...he now is alive but he wasn't originally so haven't they changed the future with this because James being alive would have consequences wouldn't it? I mean it is technically a paradox because he shouldn't be alive and if he had kids they shouldn't either...I hate time travel (hide spoiler)]. 
 I will admit the last book is my least favourite, the time scale is a bit unrealistic I mean it's set over like 2-4 weeks and the plot really confused me at times which sucked.