I have thoroughly enjoyed Wen Spencer's Ukiah Oregon series, so when I heard that she would be writing a fantasy standalone with a bit of a romance, I penciled Tinker right in on my Must Read list. I didn't know what exactly to expect, but I thought it would be good.

Tinker, our title character, is a teenager in an alternate universe Pittsburgh. She lives on Elfhome, a world that overlaps Earth at Pittsburgh via a faulty hyperphase gate that opens every 28 days and returns the city to Earth for fresh supplies. Unlike Earth, Elfhome has strong magic, which poses a major problem for Tinker when in the first few minutes of Shutdown Day, Windwolf, an important elf, stumbles into her scrap yard chased by hostile wargs. How can she save a magical being in a magic-less world? A battle ensues, and in order to save Windwolf's life, Tinker must use all her resources - mental, emotional, mechanical, and, yes, magical.

By the time the dust settles and the gate is powered up again, Windwolf has come to two conclusions. The first is that he owes Tinker an enormous debt, and the second is that someone is trying to kill him. The way he deals with both of these circumstances bind Tinker and him in surprising ways. Tinker must decide whether the changes he enacts are ominous; while at the same time trying to understand what precipitated the plot on Windwolf's life.

If the above sounds confusing, it won't be when you read it, though Spencer packs a lot of action and physics into her story. The scientific explanations of how the hyperphase gate works and how Earth and Elfhome relate to each other aren't easily understood unless you've just come out of Physics class, but as far as the story itself goes, everything was perfectly comprehensible.

Though Spencer is very good at moving her tale along and weaving together various story threads, the most enjoyable aspect of this book is Tinker herself. Tinker is brilliant, a mathematical genius, but she's also very young, and so she's not arrogant in the slightest. She's still working out what her place is in her world, which gets more and more complicated as the story progresses. Tinker is also brave and fierce. What she doesn't have in physical bulk she more than makes up for in intelligence, so she is able to protect herself and those around her. She's also emotionally whole - she has a mother figure in her scientist friend Lain and a male cousin, Oilcan, who's more of a brother to her. All of these characteristics make her sympathetic to the reader, and it is easy to root for her success.

The other characters aren't as well developed as Tinker, however. Windwolf was intriguing, if somewhat underutilized. It was interesting to see the differences between elfin and human societies. Spencer's elves have a distinctly Japanese quality, and Tinker is definitely all-American tomboy, thus the collisions between the two cultures resulted in some rather large misunderstandings. Two other characters, Tinker's friend Nathan and her employee Riki, had real potential as secondary characters, but unfortunately both were shelved by Spencer before that could bear fruit.

Spencer's books are chock full of twists and turns and chases and fighting. The book is very hard to put down, especially in the beginning when Elfhome and Windwolf are still unexplained and mysterious. The romantic bits Spencer includes are just enough to annoy the stereotypical romance-hating straight SF/F reader, but also enough to pull in your average romance reader. Still, a bit more emphasis on Tinker's relationships would have been a bonus. In the book's last half, the story becomes increasingly plot-driven, which was somewhat of a disappointment.

Though I wished Tinker could have been slightly more romantic, Spencer tells a good story with an original and completely likable heroine. The author seamlessly blends fantasy, technology, science, romance, and adventure, in a way that should make her accessible to most readers. If you haven't tried her yet, please do.