The main problem plaguing Rhen is that an illness is spreading amongst the Lowers which paralyzes and kills the victims- and her mother has contracted the disease and only has a matter of time left. Rhen and her father are hard at work on a cure, but with their limited resources, it is difficult to develop and test. Rhen would love to be a scientist at the university, but it is not within the realm of possible, as she is a woman. Her cousin and confidante, Seleni, is an Upper and her aunt and uncle frequently invite her (but not her father) to their parties. Rhen finds the opportunities useful to try to convince the people in power to look into the illness, but her pleas are useless as the disease only affects Lowers thus far.
Every year, there is a scholarship contest to allow one "gentleperson" entry into an elite university, and the young men all compete. Holm, the person who runs the contest, is an enigmatic recluse and no one knows much about him, except that he is full of magic or inventions and then contest is unlike anything else. Of all the young men who enter the Labyrinth, only one will emerge the victor, usually an Upper. Occasionally, people will die in the course of the contest. This year, Rhen has decided to dress as a boy and try her luck, the invitation does not specifically exclude her. With Seleni by her side, they enter the contest not knowing what to expect or what will await them.
In a fascinating journey, we follow Rhen and the other characters as they face the mysteries and dangers within Holm's Labyrinth. This was impossible to put down and absolutely engrossing- I was fully enveloped in this world and contest. Rhen was a great character, but so were many of the side characters, including Seleni who is brave and fun and whose greatest desire is to marry Beryll, a young man of character whose parents are very picky. There is also some diversity in the cast, although the labels are not known by the characters, with Rhen being dyslexic and Lute's brother Ben seemingly autistic (I am assuming what the diagnoses would be as they are not named).
Additionally, a love triangle between Rhen and a Lower and an Upper adds an interesting element of romance to the story (though her desires are readily apparent). The romance was really beautiful and I won't give any quotes (though, oh my goodness, the swoon!) or details to avoid spoilers, but I really enjoyed it!
There are also a lot of interesting and relevant themes in the book, including the feeling of "other" in medical care (we don't get that disease so not worth bothering with), decisions made seemingly for good which can destroy livelihoods (restrictions on fishing made by Uppers which impact Lowers), socioeconomic divides, and sexism to name a few.
Overall, this was a really fascinating and wonderful adventure, and I am extremely eager to read the next book in the series. I highly recommend for all lovers of YA fantasy.