A boy and his older brother hatch a plan to return to the moon for the fourth time in their homemade rocket. This time, they're going to build something extra-special. Using a bunch of "junk" their mom left in a heap by the back door, brothers Fox and Dodge Wilder blast off by night for their fifth trip to the moon. They strap into their old car-seats and put on their protective bike helmets and winter coats. Ready for lift off! When they land, they set to work on a magnificent fort. It's hard work, and sometimes they face setbacks, but Dodge knows he can always turn to his older brother for inspiration. When they're done, they return to the comfort of home and breakfast Did the trip really take place, or was it only in the kids' imagination?