In keeping with Bill Martin Jr.'s worldview (the book is published under his imprint) that the imagination is unlocked through the sheer joy of language and further fired by strong imagery, Mandel (The Official Cat I.Q. Test, not reviewed) has written a simple, playful text -- much like Martin's work, with two words per page and the couplets rhyming on every other page -- to accompany Mackie's cats. The activities, gestures, and behavior of the cats illustrate the ideas of opposites and distinctions: hot/cold, up/down, day/night, red/white. Most of the images are very successful, although a couple -- shy/bold, farm/town -- are placed in a slightly obscure context. Mackie knows how to draw the eye right where she wants it on the page through bold, uncluttered painting. Her cats are utterly appealing but maintain an edginess: The darkly shadowed eyes and Cheshire grins suggest a none-too-distant lunacy. Snappy and humorous, encouraging of many return visits.