Guardian's nightmare

"Charlee Smelton is an average thirteen-year-old girl struggling to adapt after her family moves to San Francisco. She thinks her biggest obstacle is facing the bullies who brand her a nerd and a dweeb. She’s wrong. Her life is about to change—for the worse. First, she receives a gift of the ugliest, most old fashioned bike she has ever seen. Try as she might to ditch it in the city, she just can’t seem to escape that very mysterious two-wheeler. Then come the visions of a world across a dimensional divide, a princess in fear for her life and a dark knight pursuing her. Are they just dreams or something more? For Charlee, everything she ever thought she knew about herself soon crumbles as she starts down a path to discover her true self, and she will need that hunk-of-junk bike more than she could ever imagine. Without it, she might not be able to find the hero in herself—the hero she must become to save her friends, family, her city—the world—from an evil only she can defeat. An evil she allows into this world.' --Provided from Amazon.com.