Explores the architecture and building processes, as they are being rediscovered, of Gothic Cathedrals in the Middle Ages.

Beakman explains that construction equipment is "strong" because of hydraulics. He demonstrates that when you try to compress a liquid, it has a limit. Pascal's principle says that the pressure is the same everywhere in the liquid so if you open the end of the syringe, then the liquid is forced out. Using this, they show how Liza can push down on one hydraulic shaft and this will cause the rat to be lifted. Basically, she does more work with less energy.

After Charkie ruins the audition for a play, George comes up with a plan to stop it from happening again. He ends up building a drawbridge using the resources around him.

Tired of the Man with the Yellow Hat's house rules, George endeavors to build a tree house to set his own rules. George has to figure out the right way to build his tree house including obtaining the right materials and construction method.

On the Mel Dorado Show, the host explains the story of Sir Miles Axlerod, a billionaire who found Allinol, an alternative, clean source of fuel. Sir Miles Axlerod joins the host on the show and states that alternative energy is the future.