With the intruder captured and having realised rescue is no longer a certainty, the boys decide to pimp their island paradise even further, by adding hydroelectric power to their beachfront treehouse. Tory wants the electricity to signal passing ships but Richard has home comforts on his agenda

As Tory channels his despair into making distress signals, Richard does his best to cheer him up by designing an automatic fish-catching device and a range of ‘4th of July' inspired inventions. But will they see all their hard work go up in smoke?