Companions. Unseen Things, #13

In an effort to get out there and prove themselves to the others, Alarwyn and Stephanie head off to the Reptilian dimension to do a little exploring, but things take a serious turn when they discover a zethichtalarin plot to destroy the nathalis homeworld. Now they must come up with a plan to stop the plot and kill the conspirators before they can bring their deadly plans to fruition. Unfortunately, their plan involves being gone for an extended period, as well as having to deal with the zeths all on their own, which causes Giles and Savaric no end of worry.
Also, when the hybrids start aging at a rapid pace, and the scientists at the base are clueless as to what's causing it, much less how to stop it, Colonel Swanson shows up at the house to ask Charles and Richard for their help. Unfortunately, without knowing the cause of the aging, there may only be one way to save their lives, but getting them out of the base, and then figuring out what to do with them afterward are two hurdles that must be overcome before they can move forward with any solutions.
Lastly, while dining at a restaurant together, Derek and Jarrod meet a waitress named Darla, who becomes instantly obsessed with Derek. Unfortunately, this causes him no end of trouble when he runs into her at a club later, and she very physically thanks him for the generous tip he gave her...right in front of Tina and the others. Controlling her temper, Tina informs her that Derek isn't available, but offers to introduce her to his brother Logan instead.
Could this be a chance for Logan to fall in love again, or will the emotional scars of his past get in the way of his future happiness?Companions is book 13 of the Unseen Things series.