Add a super squirrel to the usual holiday sugarplums with Newbery Medalist Kate DiCamillo’s delightfully tart new novel. Much like its furry hero, this swiftly paced tale is full of bold leaps and surprising turns. And the antagonist — 10-year-old Flora’s mother — is a bit of a nut. She’s a romance novelist “so in love with her books about love” that she frequently ignores her daughter and beleaguered ex-husband. In early chapters, a squirrel’s tussle with a vacuum cleaner (and subsequent rescue by Flora) imbues him with super-strength, intelligence and poetic talent. Flora is sure that, like her favorite comic-book character, Ulysses, as she names him, will fight evil and protect the weak, but perhaps his greatest power is his ability to breach this lonely child’s emotional barriers. Forcibly separated, squirrel and girl search for one another through a long, difficult night and, in the process, create a ragtag, endearing community that includes the owner of the vacuum cleaner, her temporarily blind nephew and an elderly philosopher with a mysterious past. K.G. Campbell’s occasional drawings supplement the narrative and brilliantly interpret the characters, from the partially bald Ulysses to chain-smoking Mom. As with her previous big-hearted novels (“Because of Winn-Dixie,” “The Tale of Despereaux,” “The Magician’s Elephant” ), DiCamillo proves once again that “astonishments are hidden inside the most mundane being,” and gives us another fantastic story.