Big accidentally whacks a ball into The Mysterious Woods at the bottom of the garden. Small is fascinated by these woods - so they load up their truck to explore this unknown part of the garden and retrieve the ball. Small finds the trees scary, especially when Big wanders away to pick up the missing ball and leaves him alone in a clearing. Small hears birds cawing in the trees and, imagining monsters, hides in the truck - where he promptly falls asleep. Big returns and doesn't realise that Small is dozing in the truck. He thinks his friend's probably wandered home and so he tows the truck back to the house. Later, however, Big wonders where Small has gone, hoping he's not lost - and is shocked when Small suddenly appears from inside the truck asking where are they! They decide to stay indoors for the rest of the day and play a board game. Sometimes indoor fun can be as much fun as playing outdoors. Big and Small venture into Mysterious Woods for the very first time.