On the way to another adventure, Scrooge accidentally crashes Launchpad’s plane – the Sunchaser – onto a mountaintop, leaving it balancing on a precipice and causing Beakley to confront him about how he regularly endangers the family. Meanwhile, the kids continue their investigation into Della’s disappearance, but the adults eventually stumble upon it. In the end, after Dewey endangers himself for a clue, Scrooge comes clean: Della stole a spaceship he built for her – The Spear of Selene – and disappeared into space, causing Donald to cut ties with him. The boys blame Scrooge, and the resulting argument causes the plane to crash. Upon returning home, the boys move back in with Donald while Beakley takes Webby with her on an extended vacation, leaving Scrooge alone once more.
