A FIERCE AND SUBTLE POISON was absolutely wonderful! I loved the writing, and as soon as I started reading, I couldn't put it down! I had to actually force myself to go to bed so that I wouldn't be exhausted for work in the morning. :P 
 I loved Lucas as the narrator, and found it refreshing to have a male protagonist for this story. His perspective kept the story moving at a quick pace, and I really enjoyed seeing the story from his point of view because he was almost as much of an outsider to the culture as I was. I loved the mystery surrounding Isabel, too, and I think that's why I loved that Lucas was the narrator. I liked not knowing what to expect from Isabel, so Lucas was perfect! He also was completely unapologetic in his womanizing ways...and I actually found that I appreciated that. He was upfront with both the girls he fooled around with, and with the reader when he told us about them. :P 
 As for the plot and the story itself, I absolutely loved it all! I really enjoyed the Puerto Rican stories, and loved the magical realism of the story. I don't often read mysteries, but I thought the mystery was really well done, too. It was intriguing, and definitely kept me guessing. Lucas was also a bit of an unreliable narrator sometimes, so that made the mystery even better! The ending was a little bit open-ended, which I'm not a huge fan of, but I think it reflected the magical aspect of the story extremely well. Just like Lucas, we don't know what magic is really possible in his world...and it left me extremely curious and excited to see what Samantha Mabry comes up with next! 
 Overall, I absolutely loved A FIERCE AND SUBTLE POISON. It was captivating, and incredibly unique. I loved the characters, and the story was well-written and extremely interesting! It was also super refreshing to see a story set in Puerto Rico, and I loved hearing the folk stories and how Spanish was woven into the dialogue of the story!!! I'd recommend A FIERCE AND SUBTLE POISON to fans of magical realism, and also to readers who are looking for some diversity in their YA!