Sequel to Red Thunder, but set 20 years later. The kids from the first book are the parents of the kids in this book. And the kids in this book spend a lot more time as baggage than their parents did in the earlier adventures.
This book also lacks the single story arc of Thunder. The first half of the book shows the family heading to Earth (from Mars, natch) to attempt a rescue of grandma from her Florida hotel in the wake (heh) of a major Atlantic ocean tsunami. The afterword of the book reveals that this part of the book was written before the 2004 tsunami and long before the Katrina fiasco. In light of that, the book is astoundingly prophetic both about the scale of damage from such an event and the utter lack of preparation for dealing with the aftermath.
The second half of the book is about a corporate and governmental man hunt in the wake of the disappearance of the quirky genius Jubal from the first book and the impact of another of his physics-redefining inventions.
The book is fun reading, but the resolutions of both halves of the story left me rolling my eyes at implausibilities.