This story is about Lili, a sin collector who after 100 years of performing her collector duties has decided to settle down. Sin collectors are immortal beings that collect sins in order to allow people to die in peace. Lili owns an apartment, a cat and she has a job at a library. Everything seems very mundane until her old friend William shows up where she works looking for her boss. He has been researching the purpose of collectors and asks Lili to join him in Ireland in his investigations. William tells her that everything she has been told in the past by her mentors is a lie and that she and all collectors have a choice between whether they perform their duties or live a normal human life. Tempted with the possibility of starting different type of life and having a change of scenery Lili decides to join him. Before their departure they decide to pay Lili's boss a visit to see if he has any useful information around. In an unexpected twist they stumble upon a crime scene which seems to be linked to their kind and makes Lili more interested in joining William to discover what is actually going on. What Lili discovers is far more complex and threatening than what she had imagined.I loved this book. The writing was really good although there were a couple of mistakes in grammar (Still I'm no one to judge on that subject, I suck at writing in both Spanish and English). The characters were interesting and well thought of and I found the whole story refreshing. I had never heard the concept of Collectors before so I found the story quite unique in that sense and it was interesting to see what sort of powers these beings had. I also enjoyed the fact that the story kept you guessing. The main and ongoing theme of the story circles around trust. Lili finds herself confused about who to trust...should she trust her old childhood friend Billy who turned up all of the sudden after 100 years? or should she trust her old mentor Olexander who she also hasn't seen in a really long time but used to know really well? I find it easy to empathize with Lili's plight because they both seem trustworthy but also raise the same amount of suspicion in her heart. She's not some confused teen who doesn't know where she stands...She is a 120 year old "woman" who wants to be able to trust these men but can't necessarily bring herself to do so. Lili is a strong-willed and funny character; I really liked her and I found it easy to see life through her eyes. Another reason I think this book is great is because it has many twists and turns....there are many things that you might expect to happen and then there are others that will leave you quite surprised!I really recommend this book, the story is really good, unique, and totally worth the read!**Unimportant spoiler** (Though I should announce this anyways...some people really hate spoilers)...In my silly little mind I was really sad that Lili left her cat behind... I know it was hard to take the cat to Ireland but it still broke my heart to see them part. I do wish she would have tried to get him back in the end.