Don't expect a story with a heroine who is perfect in every way and too good and pure to be real. Don't expect unbreakable friendships and a long lasting love. Don't expect a fight using the most honorable methods. There is death, lies and betrayals. 
 The truth is that each one of the characters is flawed and has a dark side that shows. Adelina, our main character and a survivor of the blood plague, is scared not only physically (she is missing an eye and a scar covers the socket), but emotionally. Her father was violent and verbally abused her throughout her childhood, setting the foundation of her dark side. She is vengeful, ambitious, and mistrustful. Her power, which awakens in the face of danger and reveals her young elite identity, feeds on the fear of those around her and allows her to create illusions. 
 The other characters are no better: a vengeful prince who was removed from the line due to being a malffetto, a male prostitute who spies and finds sponsors from his bed, a fanatic general manipulated by a deceitful queen, and many more. 
 And I love them. I love the dark side the characters have. It makes the story fresh and real. 
 The Dagger Society, led by the prince, is a group of young elites who fight from the shadows to return the rightful heir on the throne. They rescue Adelina from her execution because they sense her great power and want her on their side. However, let's face it; their methods are not the most honorable ones. They fight guerrilla style and some may even be considered terrorist attacks (view spoiler)[ Come on, how many innocent people did they kill by setting fire to those ships? (hide spoiler)] 
 Although Adelina considers these new people her friends, she doesn't trust them (view spoiler)[ and even betrays their plans (hide spoiler)], all for the sake of her sister who has been kidnapped by Teren. The thing is, they don't trust her either. 
 Adelina notices her dark side and fears it, but everything she experiences in this book makes her stronger and she starts to accept it. 
 I think the book served as an introduction and setting to explain Adelina's personality, because I fear she won't be the usual heroine but an anti-hero, a villain, and her dark side will consume her.