LOVED THIS!
First things first, to truly enjoy this, you're going to need to let go of the Carmen from your childhood. It's just that simple. If I, someone who grew up loving the cartoon, the live-action show, the computer game, and the board game, aaaaand who had no qualms dressing up as Carmen for Halloween as an adult (are you catching the fangirl theme here?), can enjoy this, then you can, too.
So there's an entirely different storyline (she's no longer a rogue ACME employee who took up with VILE), and she's been made into a much nicer person, but this is still totally engaging. She's just more explicitly kinder and gentler than there were hints of in the original series. Anyway. There is a lot of heart and humor in the book--touches like saying VILE stood for Valuable Imports, Lavish Exports, was hilarious. The random mime was a treat.
I liked how they re-interpreted Player--it worked for the context of the book, and I really enjoyed her fellow students. Making the villains sympathetic added a level of nuance that you don't always see in children's books. The staff were great as well. The academic in me however, wants to know why some are professors while others are instructors. Did the mere instructors not receive their Ph.D. in Villainy? As I think about it, all of the characters felt important and not just like scenery. I even liked the beleaguered French inspector.
The back-and-forth between the past and present was effective, and done in a way that made you look forward to the next section, so much so, that I didn't want it to end!
On a final note--Lambkins is such a cute name! Overall, a surprisingly cute and clever take on Carmen, and it makes me want to check out the Netflix series. Also, I totally need someone to write an adult version of this book, because even though they kept describing Carmen and Gray as being like siblings, I totally could see them as an ill-fated couple.