Once a Villain is the final book in the trilogy Once a Monster. Vanessa Len's third book continues the story of Joan, half monster half human and Nick, former Hero and monster hunter. After failing to stop her sister, Eleanor, Joan and Nick must continue their battle to restore the timeline. The world Eleanor has created is a dark and tragic place where humans are expendable. Life is owned and can be taken from humans at will by the monsters at their pleasure. Joan, Nick and their friends must find a way to stop Eleanor before her new timeline destroys them all and throws them into the void. This third novel is best read as part of the series. The many twists and turns of Len's series will cause you to pause and reflect on the past events and wonder at the complexities of the relationships that develop through this amazing worlds she has created for her readers. More than any books I have read, this series cries out for a movie adaptation!

I cannot express the roller coaster of emotions that I felt through this book. To preface, the Only a Monster series, is one of my favorite series. It is one of the most underrated series that has come out in recent years. It makes me terribly sad that more people have not has the joy of experiencing it, but I make sure to promote it any chance I get.

Once a Villain is the third book in the Only a Monster series, following Joan, a half human half monster girl, in a world where monsters travel through time by stealing that time from human life. To travel a year in the past, a year of human life must be siphoned from humans. Joan is caught in the middle of two worlds, and several timelines. Once a Villain, is the conclusion to the journey that Joan and her friends have been on to try and correct the manipulations of the timeline, not only to save the ones they love but also to save the whole world.

Time travel is a tricky thing to write, but Vanessa Len does such an amazing job with it. Not only does the time travel elements not complicate to much, but the keeps into history that we see is just magical. The world building in this series is so beautiful. Len’s writing is amazing in so many ways, but my favorite part (apart from the history) is the character dynamics. Her writing helps you to build such a strong connection to the characters in this series, that when their heart breaks so does yours. The family and found family elements are also so beautifully written.

Once a Villain is the conclusion we were all waiting for, but in the same respect the one we dreaded, because the series is over. I would love to believe that there is room to continue the story in this world, with these amazing characters, but I won’t get too hopeful. As far as the love triangle, I think most of us saw this coming after book two, but some may be surprised. I was pleased with the ending, other than there just not being more book.


This a YA fantasy book, but there is a closed door romance scene. (Those who know, know what went down, but this is no descriptive language).


I received an Advance Reader Copy of this book in exchange for a review. All opinions are my own. Thank you to Netgalley and HarperCollins for sending me an ARC.

Thank you, Harper Collins Children's Book and NetGalley, for the chance to read this book in exchange of an honest review.

Joan had failed to stop Eleanor and now the world created is a world where monsters rules and humans are preyed on. Nick is tormented by the choice he made, choosing to save Joan instead of stopping Eleanor and Aaron, the powerful heir of a monster family, has to fight between his feeling for Joan and for...someone else.
Helped by Ruth and Jamie, they have to navigate a monster world, where they don't know the rules and trying to fix the timeline, before it's broken forever and they will all fall into the void.

I LOVED reading Once a villain. It starts right after the devastating cliffhanger of the second book and I couldn't love more Joan and her friends, between rivalry, jealousy, bickering and survival in a world ruled by monsters. The book is filled with twists and surprises, new and old characters, characters belonging in different timelines, a love triangle (that was uniquely solved and I truly loved it) and the fierce love that connect all the characters, determined to get back to their timeline or to fix this horrible one where being human is dangerous and they are treated like slaves and abused on.
This book was an emotional rollercoaster and I loved every single page and I can't wait to hug my copy!
It's the perfect ending of a perfect trilogy! Vanessa Len is amazing!

4⭐️

Thank you to HarperTeen and NetGalley for an e-ARC copy!

Y’all, this book series is incredible, I very much recommend reading it. I had pretty high expectations for this third and final book, and while it wasn’t as perfect as I’d hoped it’d be, I still had a lot of fun reading it. There was one decision towards the end of this book that I did not really like; it just felt like the author was taking the easy way out of the situation. But I will say, I much preferred this decision over the alternative.

I can’t even express how much I love all of these characters, they’re so incredible. 💕
Aaron was always my favorite character, but I grew to like nick so much in this book too. This book leaned more on the character side than the plot, but everything was still so interesting; I’d say this series came to a pretty satisfying conclusion. And it very much reminded me of The Umbrella Academy show (saving the world and all that).

I have lots to say about this book, but I mustn’t spoil anything until it comes out 😭

I’ve been waiting for this book since I first fell in love with Vanessa Len’s ONLY A MONSTER TRILOGY, and Len truly does not disappoint. ONCE A VILLAIN ties up the story with fanfare and flourish, keeping readers on the edge until the very last page. My only gripe is the way the love triangle played out, which I can see plenty of fans responding to in spirited ways, but overall, this is a sensational story.

Vanessa Len has done it again - Once a Villain is a fantastic, emotional, and wildly original finale to one of the most creative YA fantasy series I’ve ever read.

This world, where monsters manipulate time and morality isn’t black and white, has hooked me since book one. Vanessa has created a magic system and plot that feel so unique, and that originality continues until the final page.

The ending really surprised me in the best way, it’s very bittersweet and unforgettable. There is a certain aspect of the ending for the three main characters I probably wouldn’t have chosen. However it definitely has lingered in my brain, and the more I think about it, the more I admire how perfectly it fits this story and how it wasn’t what i anticipated.

Character development is where this series truly shines. Joan, Nick, and Aaron all grow in big, sometimes painful ways, and the dynamic between them in this book had me glued to the page. And the background characters? Vanessa makes every one of them feel real. I would read spin-offs about literally any of them with no hesitation.

Like the first two books, this one is fast-paced and intense. At times I had to put it down just to breathe. It’s that nonstop.

I’m devastated that the series is over, but I can’t wait to see what Vanessa Len writes next and I’ll be first in line.

4 Stars!

Thank you Netgalley for the ARC, when I received the email of the approval I almost screamed since this was one of my most anticipated releases of the year and was way too impatient to have to wait until August.

First of all I need to say, why isn’t this series more talked about because it is truly one of the most underrated YA fantasies. The writing excellent, the characters emasculate. I could go on and I will later on when I am yapping about it to everyone I know.

It is bittersweet to say goodbye to a series you have been there from the start. But I am so happy too because when It comes to a trilogy or any series the final book can really make or break it for you. And of course Vanessa Len did not disappoint (as I knew she wouldn’t). As if Joan, Aaron and Nick have not been through enough already, they really go through it in this book in particular because not only are they basically trying to save the world as they as it but they are also trying to figure out they VERY complicated relationship. And of all the ways I thought this book was going to end, THAT was not what I was expecting at all and I am definitely not mad about it. In fact kind of refreshing to see this take in a YA fantasy.

This was a wonderful conclusion to Joan’s story. I really felt like we still had plenty of action and timeline shenanigans to uncover, love triangle resolution and a lovely HEA.

thanks to NetGalley for the eARC

⭐️=2.25 | 😘=3 | 🤬=4 | ⚔️=3.75 | 15/16ish+

summary: Only a Monster book 3 (finale to the trilogy)

thoughts: 🚨🚨🚨🚨🚨spoiler-ridden review!! beware!! 🚨🚨🚨🚨🚨

- WHAT IS THE SIGNIFICANCE OF THE PIN AARON GIVES HER IN BOOK ONE WHAT IS THE SIGNIFICANCE U NEVER EXPLAIN IT WHY IS IT SO MEANINGFUL TO AARON IN EVERY TIMELINE WHY I NEED TO KNOW

- this was plotted out so haphazardly?? literally on the last page there’s this joking line of dialogue like “hey you still owe the Lius two favors” and everyone is like “lol!” but this is NOT lol this is a serious unresolved plot thread from book one!! like did you know what you were going to do with that when you wrote it, Vanessa?? why did this go ignored??

- also the fact everyone has been resurrected via different timelines at least once, sometimes way more times than that, made the emotional stakes of this book, like, zero? because now I know that none of the characters I am supposed to care about will die, and if they do “die” they can easily be alive again. I realized this partway through the book and then the rest of it was, like… consequently dull.

- I understand that a throuple is thematically necessary to resolve everything—human vs monster, where do you find a place to belong when you’re stuck between two worlds et cetera—so having a throuple with a human, a monster, and a human/monster (rather than traditionally resolving a love triangle) answers that question, and that’s fine, and that could have worked, but I truly canNOT believe that the Aaron and Nick of this timeline would be able to fix their issues (like Aaron being responsible for the thousands of years of human death and that being specifically against everything Nick believes in) enough to enter a romantic and sexual relationship between the two of them, let alone alongside Joan?? like these are TEENAGERS they’re not going to get over their trauma (that distinctly pits them morally against one another) over the course of the one book??? I get the underlying intent but it is impossible to follow through in a believable manner under the circumstances with these guys specifically. I don’t believe it.

- I hate the circumstances under which Joan and Aaron have sex. Joan was not in an emotionally safe place, and it was such an irresponsible circumstance and it gave me the ick

- the sad thing is that the first book of this series was SO perfect. and this is so not and was clearly unplanned bc of all the unfinished threads—both literal plot things and character development. rest in peace Once a Villain, you would have loved being a strong ending to this trilogy!! tbh I feel like this should have been four books, or at least extended so that we got flashbacks to alternate timeline memories between Eleanor and Joan bc then we would care more about them and the stakes there and therefore things were not set up deliberately and it’s just maddening!!

This was such a fun read! This series was such a great series and full of great world building and plot twists.

I absolutely adored how this book wrapped up the series.
Without getting to spoilery, the love triangle concluded in the best possible way and I wish more authors had the nerve to go the route that this did.

I was on the edge of my seat the whole time reading this, the pacing is fantastic and the action scenes are thrilling.
Anything involving time travel can get messy and convoluted, but I think Vanessa Len executed it beautifully across this series. I look forward to future books from her.

The Monsters trilogy is seriously the most underrated book series and I hope more people discover it.

Thank you HarperCollins Children's Books and NetGalley for this ARC!

I'm obsessed with this series! Such a good finale! Every thing got wrapped up in a satisfying yet surprising way! I could not have predicted how it ended, and that's what made this so good to me.

Thank you Netgalley for the ARC of this book!

This was such a satisfying finale for the story. It was fast paced, kept my interest, had a twist that had been building up among the whole series that you realllly had to be paying attention to in order to notice the signs of.
Vanessa Len does such a good job in her descriptions to make you feel a part of the world regardless of what time period they are in. Looking forward to what she comes up with next, but this was such a satisfying end to the Monsters trilogy.

*spoilers for first two books in series*

OMG, what a way to end this trilogy!

This book starts immediately where the second book ends, so I'm really glad that I reread before jumping into this one. While it does give you hints throughout about what happened in the previous books, it was still really nice to have it fresh in my mind.

In this one we have Joan, Nick, Aaron, Ruth, and Jamie all in a horribly dystopian future where monsters rule. It's a wild mishmash of times, though, with electric cars, but Tudor style buildings, public executions, and, most importantly, the original London Bridge.

Throughout the book we learn so much more about Joan, Aaron, and Nick's families, as well as more information about what happened between them in the true timeline. It was great to get these glimpses, as well as to see how things might have been different in this new timeline.

I really loved how Vanessa Len wrote Aaron, who is usually so confident in himself. She shows a real vulnerability in him that I really appreciated. I think we see a bit of it in the first book, but then in the second book he's quite stuck up, as his father wants him to be, but we really get to see his true self in this third book.

I really love the themes that are woven throughout the trilogy and the way that Joan fully realizes her own identity. And the way that the book titles reflect this. In the first book (Only a Monster) we have her discovering that she's a monster, time traveling, and doing everything she can to bring back her monster family; in book two (Never a Hero) we see her in a hero role, having saved her monster family and unmaking Nick, but at what cost is she a hero (maybe she never was)? In this third, and final, book (Once a Villain) we see Joan really struggling with her role in the events that have taken place over the course of the three books, she feels that she's a villain because Eleanor has said that all that she's done is because of Joan. So this new, dystopian monster world is because of Joan, because Nick chose her over the entire world, and she has a lot of guild around that. I like how she comes to terms with it and the growth that we see in her, both over the course of the trilogy, as well as in this book specifically. I think that all three of the main character see a lot of growth in this last book and it was great to witness.

Pretty much every one of the questions I had going into this book were answered and I'm so happy with the way they were answered. Len did such a great job of wrapping up the loose ends and giving a really satisfying conclusion. Once a Villain was an absolutely jam packed, wild ride of a book, but it was absolutely perfect. I'm already looking forward to rereading this trilogy soon!

I love a bit of time travel, and this series has been an excellent ride! I'm still not sure I totally understand all the rules and limitations, but the plot was good enough that I could suspend my disbelief whenever something wasn't quite adding up. I love Joan, and thought this was probably the strongest book of the series? Overall it was a really satisfying conclusion to a brilliant trilogy!

Also, that cover is absolutely stunning. I don't usually like people on covers, but this one is gorgeous.

Thank you to the publisher for providing a copy for review

ARC provided via NetGalley in exchange for an honest review. All opinions expressed are my own.

➳ 4.5

This is how you write a finale.

I'm trying to figure out how to review this as it's an ARC and the final book in a series, which leaves my hands a little tied on what I can say. What I will say is that it is taking everything in my power not to write the most incoherent, spoilery, praise review because holy crap; this was such a good ending to this series.

I really liked book 1. It was unique and fun and reminded me a lot of more nostalgic YA book series, complete with an angsty love triangle. What I wasn't expecting from book 1 was how much this series would grow and change with each book, becoming something much bigger and better than I originally anticipated.

This book is a roller coaster. If you've loved this series, you're going to adore this finale. It's a perfect conclusion, from the plot to the relationships (the relationshipssss. guys, you aren't ready) to the individual character growth.

If I had to critique any of it, I'd say that the villains sometimes felt a bit childish, the ending was a bit rushed, and there were a few things I would have liked clarification on, but there was a lot that happened at the end and I understand.

Overall, this was fantastic and I'm incredibly impressed by Vanessa Len.

While I truly loved the first book in this series as it progressed I found myself not as invested. I was hoping for Once a Villain to expand on the characters and improve, but sadly the problems that I had with the second book persisted. There was a lot of repetitiveness to the point that I couldn't enjoy the story. There was no character depth. Her cousin felt like background and flat in this one. I just didn't enjoy it as much as I thought I would, sadly.

What a disappointment! I absolutely loved this series and was so excited to read this but it’s terrible on so many levels. Warning spoilers ahead. This series had magic and such a unique world that drew you in but this book is boring and repetitive and feels like it was written by an entirely different author. The moments between Joan and Aaron were beautiful in the previous books and the entire series had a sweetness to it despite the monstrous world it was set in. Until this book. I’m angry the author and her publisher completely changed the tone, content and explicitness of a series that is marketed as 13+. How disgusting for the young girls like mine who loved the first two books, and their unsuspecting parents, when their daughters read this book pushing the idea of a three way anything as appropriate for young readers! I did not want to read that and it is not at all how the series has been. I actually thought the author did an impressive job not pandering to anything in this series. Jamie and Tom are gay men who are married and at different points desperate to get back to each other. They are in love and that’s it but like Joan’s relationships in the previous books it was never inappropriate so I do not understand why they decided it was ok to do this now. What a horrible way to end this series and it takes up all the story.

I won’t be rating this on goodreads or publicly right now because I don’t feel like I can give a genuine, fair review. I feel robbed and annoyed in the fact that we had a love triangle that didn’t resolve in the way I expected, and it really felt like a cop out to me. I don’t think I will be the only one,

I hope you understand, but I don’t feel like I can post this much annoyance anywhere right now without people picking up on spoilers either. I wouldn’t want to spoil or hurt the release before it’s out with my personal and very biased opinion.

*I received an advanced copy from NetGalley*

I just finished the book 10 minutes before writing this so my feelings are a bit all over the place but it. is. good! I really enjoyed this conclusion to the monster trilogy, I think it wrapped the books up very well. You can expect the same type of banter, heartwarming relationships and plot twists found in the other two books, as well as some more context and exploration into the world of time-traveling monsters and timelines. The LORE went hard and I loved that.

I reread the first two books before reading the arc so I had full context, but it isn’t fully necessary as the author does a good job recapping throughout the book.

There has always been a bit of a love triangle in this series and I will not spoil anything- but I will say I was surprised with the direction of it. I will have to process further and let my feelings settle on it.
I’m very interested to see what might differ in the final copy (small or not)! I will be reading it, AGAIN 🤪, on release day. This is one of my favorite series I’ve read and I will not! stop recommending it to people! Take this review as your personal recommendation from me 😙🥰