Sarah Beth Durst loves fantasy, and she loves cats. In “Catalyst,” she combines those loves to create a kitten that grows and grows and grows. When almost twelve-year-old Zoe finds the tiny kitten, she knows her mother won’t let her keep it. She knows because she wasn’t able to keep any of the other animals she rescued, including the last one, a skunk.

But when the tiny kitten (smaller than her hand) places a trusting paw on Zoe’s hand, she knows she wants to help the little creature. So she sneaks the kitten into her room and gives it milk. She also immediately tells her best friend and next door neighbor Harrison about it. When Zoe finally gets up the courage to tell her parents about the kitten, her older brother Alex unexpectedly sticks up for her. He reminds them about his leaving for study abroad and says this might be just what Zoe needs to get over her funk about losing her brother. And it’s almost her birthday, so her parents relent.

She names the kitten Pipsqueak, which turns out to be unfortunate. When Zoe turns twelve a few days later, Pipsqueak starts to grow, incredibly quickly. Overnight she becomes the size of an adult cat. Nervously, Zoe and Harrison take Pipsqueak to the local veterinarian who doesn’t believe their claim that the kitten grew that much overnight. Otherwise, the now cat-sized kitten is healthy. When Pipsqueak grows more and becomes the size of a dog, Zoe is freaked out. There are also reports of a flying poodle in their town, and Zoe realizes that with such strange animal sightings going on, Pipsqueak  might be taken away and studied if she is seen. So she and Harrison hide the huge kitty the best they can.

Zoe decides her best chance to figure out what is wrong with Pipsqueak, who is now talking and reading, is to get in communication with her Aunt Alecia, who her mother says is quirky and interested in unusual things. The problem is that her mom is estranged from her sister, and the only way to reach Aunt Alecia is by mail. Not email. So Zoe sends a letter. The response from her aunt is not what she had hoped for. Her aunt says that she should bring Pipsqueak to her. But her aunt lives hours away, and Zoe doesn’t want her mother to know about the cat for fear her mother will call the authorities.

In the meantime, we get to know Pipsqueak, who must be the most intelligent and naughty — but adorable – cat ever. She loves to read and learn, and she tries to sing opera. When Zoe asks Pipsqueak how she can sing opera if she’s only read about it and not heard it, the cat indignantly responds that she has an imagination. (Hint: her attempts do not sound like opera.) Pipsqueak wants to chase birds, but listens to Zoe when she tells her that she can’t. She tries to stay hidden but is, after all, a cat, and prone to impulsivity. She’s the epitome of a cat!

How will Zoe and Harrison get Pipsqueak to New Hampshire? What, if anything, will her aunt be able to do to help them? Will she know how to return Pipsqueak to the size of a normal cat? And who can Zoe and Harrison trust to help them? The obstacles seem insurmountable, but not if you are a clever children’s author who can make the whole story come together smoothly and beautifully.

This lovely novel is sure to appeal to many varied types of readers. There are enough adorable, amazing creatures to please any animal lover, as well as an adventure that’s thrilling enough to interest any lover of action stories. And the magic (because a cat who grows to be the size of an elephant must be magic, right?) will charm fantasy readers. Zoe grows in the story as she learns about mistakes that her mother made and how her mother learned from those mistakes. She learns to trust her instincts and her friends. Most of all? Zoe, Harrison, Pipsqueak, and several other magical creatures have the adventure of their lives.

Please note: This review is based on the final, hardcover book provided by the author for review purposes.