I am late to the birthday party: this is my first book with famous 'Queen Thief' but it is number 8 of the series (I think there are some short stories part of compilations and she shares the 'screen time' with 'detective' Yumemizu in another book... (there are many, many, books with this character). But even when you jump into a series midway, the author's writing style and the quality of the story/writing, should help overcome the shortcomings of getting too late to the party.
Does this book cut the mustard, then? (Taking into account the backstory I don't have). Well...
The book tells the story of 'Queen Thief' and her attempts to bring back to life her not really dead friend and partner 'Joker' (someone has watched "The Princess Bride" too many times). She has to find a crystal that will give her the chance to raise Joker from the 'undead'. However, she is not the only one interested in it, and many invested powers are behind the 'crystal tablet' that can give life; in particular, the one 'homunculus' that left Joker in his weird state. Who will get the 'crystal tablet'? Will Joker get back his consciousness? Why are there so many characters in this book?
And that is probably the biggest problem with the story: there are so many characters, storylines and loose ends, that Hayamine jumps constantly from one place to the other without really setting into any of them. We get 15 pages of Queen Thief, 20 pages with the homunculus, 15 pages with the German secret organization... and in those pages there is a lot of shouting and silly situations, but not really any kind of storytelling. On top of that, the book (for my taste) is too violent and with too many situations of unnecessary/gratuitous violence (particularly taking into account its target readers, like 11, 12-years-old kids). Hayamine knows how to create funny situations and make the reader smile (or laugh), but here she seems too invested in juggling all the characters and creating 'dangerous' situations (guns! assassins!) that go nowhere and just extend in an endless and repetitive cycle of action moments. Hayamine should know better.
The best: the doses of humor; the characters
The worst: too much fighting, too many characters, too convoluted
Alternatives: the mystery series by the same author, featuring Yumemizu (who has a great cameo here), is better; if you like thieves, in "Meitantei Conan" you can enjoy Kaitou Kid; Miyabe Miyuki or Ranpo Edogawa's series for kids/teenagers are better.