Stinkbomb and Ketchup-Face and the Great Big Story Nickers

When bits of their story go missing, along with Ninja Librarian Miss Butterworth, Stinkbomb and Ketchup-Face decide to investigate in their own inimitable way. But who would be so evil and wicked as to nick chapters from books? Could it be a penguin? A zebra? A newspaper? Or some other fiendish black and white thing . . . ?