Holding the Fort: The Storm Follows - Hardcover

After thwarting the machines' newest attempt at taking over the world, Ethan and his squad from Blackwoods must go back to the year 1999 and destroy the malevolent artificial intelligence that started it all.

Through an epic road trip chock-full of perils and pitfalls, Team Blackwoods races to a small town outside Mount Rainier to intercept a Zyvantian space pod -- in an attempt to neutralize the alien computer virus it contains. In the race to the pod, with all of humanity at stake, the young teens will have to beat the U.S. military...and a perfect-looking family of four with sinister intentions. Then there's a very determined FBI agent hot on their trail, trying to put together the pieces of strange, horrifying crimes committed along the way by those known as 'The Trackers'.

Oh yeah, and the kids need to build a time machine to get back to the present day. Easy peasy.