The Treachery of Beautiful Things is a beautifully written book, marvelously atmospheric, but bogged down by foolish characters and a confusing ending. 
 Jenny is Tom's little sister; she adores him with a child's hero-worship for an older sibling. Tom is the favored child, tremendously talented with the flute, and when he disappears into the trees one day, Jenny and their family is never the same. She can't recall what happened, except to say that Tom got eaten by trees. Her parents never get over the tragedy, ships her off to boarding school, while their mother self-medicates the pain away. Jenny never forgives herself, but she is almost 18, about to enter college in the fall, and she braves her fear of going into the woods one last time to say goodbye to Tom. Unwittingly, she enters the fairy realm where her brother was abducted, and sets off to rescue Tom and bring him home. She runs into Jack, whom she is not entirely sure she can trust, and the book is alternately told through his and her view. 
 The good: The writing and the beautifully-created environment. Ruth Frances Long has written a book that is verbally, among the best descriptive writing I've read in YA fiction. The world of faerie, the characters, everything comes alive. The descriptions are beautiful, vivid, and never overdone. There is nothing of Dickens about it, reading the book for the words alone is purely enjoyable. 
 So impossibly graceful, it hardly looked real; rather, it appeared to have been spun from dew drops and gossamer. Ash trees lined the path leading toward it, slender and pale as beautiful maidens bending as if to tend it. 
 Now that's a world I'd like to inhabit. 
 The characters, on the other hand...not so perfect. 
 I had high aspirations for Jenny. She seemed like a level-headed character, though mentally traumatized through her experience when her brother disappeared. Initially, I thought she was brave, confronting her fear of the woods and entering them to save her brother. She does indeed to everything she can to fulfill her goal, my main concern is that the majority of her actions are foolish and rushed, that places her solidly into the TSTL category. 
 Forget her fear of the unknown, of the forest. Any time she's upset at her guide, Jack, she foolishly rushes off on her own, into a strange wilderness in which danger is inherent. After the first few situation, the reader loses much sympathy for her. And then there's this... 
 "Oh God. I don't believe I'm doing this!" She surged to her feet, trying to shelter the baby, and ran into the clearing, straight at the dragon. 
 Really, Jenny? REALLY? 
 And let's not mention the baby. This is a fairy creature's baby. It doesn't look like a normal baby. Any idiot knows not to disturb a infant animal when there's the possibility of an angry mother returning at any moment. And yet Jenny not only takes the baby, but rushes into a confrontation with a dragon AND the baby's angry fairy mother. I wish this was her only foolish action, nope, nope, nope. Jenny even admits it herself after her 10000th mistake. 
 She was an idiot, so afraid of the greenman, so angry with Jack, so thoughtless[...]So upset, so angry, so stupid and blind. 
 And then there's Jack. Beautiful, wounded, martyr Jack. And boy is he a martyr, he might as well be wearing a crucifix. Jack is plagued by guilt, he blames himself for everything that goes wrong in their adventure, regardless if it's actually TSTL Jenny's fault or not. He is a good protagonist, he's nice, he's mysterious, he's not a jerk...but boy is he a martyr. I got sick of all his guilt around the first half of the book. 
 The ending was not rushed, but I found it tremendously confusing. I couldn't keep track of what was going on, I didn't know why things happened that way, I didn't know how the characters ended up as they did. The plot and characters had too many flaws for the plot to be truly enjoyable, but the writing was a masterpiece.