<P>Even before Dad tucks him in, Samuel McKay has devised a plan to find out what really goes on in his house after bedtime?he waits until Dad has shut the light before tiptoeing out of his room with his trusted furry accomplice, Petey Bear, determined to find the truth. Sam imagines fish swimming in the bathroom pipes, a thousand toy trains in the basement, a zoo in the guest room, and a rocket in Dad's parking place. Each wildly imagined activity is highlighted on the wall by Pete's flashlight beam as the daring pair quietly and carefully creep through the house. They persist, finally reaching the den and the moment of truth. Sam's parents, of course, are simply relaxing; Dad does the crossword, and Mom is reading. Disappointed, Sam and Petey trudge back up to bed. This romping, rhyming adventure will prove once and for all that kids aren't missing out on anything special after bedtime. Or are they? In the final wordless image, Mom and Dad are eating pink ice cream and cake at a private little party, perhaps celebrating that they've won the bedtime battle?at least until tomorrow night.</P>