The final showdown between the Great Galloon and the evil crew of the Sumbaroon. Captain Anstruther and the crew of his Great Galloon have trapped the evil Zebediah and his Sumbaroon at the base of a waterfall - at last they will rescue the captain's stolen bride, Isabella! But the Sumbaroon sprouts mechanical legs and escapes over land like a devious metal spider. Stanley and Rasmussen are determined to stop Zebediah from taking over the Great Galloon, but it turns out that it isn't Zebediah who is after control of the enormous airship. Will they figure out the treachery in time? Including brilliant illustrations by John Kelly, this action-packed third book surpasses all expectations, and proves that people working together, no matter their backgrounds, can accomplish anything.