Daunted by the sheer size of this flat, featureless backyard, Jake & Joel Moss take it on anyway with a need to succeed. They turn an existing debris-filled hole into a massive, natural eco-system pond stocked with big catfish and bass--with a sandy beach, cantilevered redwood dock and giant boulders along the water's edge. Figuring out the homeowners have a child, an overhead aircraft-inspired redwood tree house will make the kid's imagination take off-if they can finish all this before the family returns.