What a nice conclusion to this trilogy!
It's been marketed as a companion series, but I think it's not the best idea to read them out of order, as you do get to see the characters and the continuation of their story in echt following book.

This last part follows the story of Gideon and Sofia, trying to bring down LaRoux Industries.
They meet up with the other main characters from the previous books, Lilac, Tarver, Flynn and Lee, and they join forces in their battle to protect humanity and the world they live in from FDI.

I really enjoyed this last part.
It was fast paced, action packed and with just the right amount of romance thrown in to make me enjoy it, without taking away from the sci-fi element of the story.