Also, as their friendship with the blue fins continues to grow, their blue fin friend Freddie expresses a desire to visit the human dimension. Looking forward to the opportunity for a cultural exchange, they're more than happy to oblige. It started off well enough, but when Freddie shows an unbelievable capacity for learning and retaining new information, they begin to realize that they may have inadvertently opened a Pandora's Box by exposing him to the wonders of the human world. Life on the island would no longer be enough for him, leaving them all with some hard decisions to make, not only about his future, but the future of his people as well.

Finally, when portals begin to open on the blue fin island while the team are there installing a new solar power station for their friends, a desperate fight ensues to stop the agaronin from capturing themselves a new batch of slaves. While they were able to fend them off this time, it quickly becomes obvious that for their own protection, the formerly peaceful blue fins would have to be armed, and then trained to defend themselves against the unpredictable threat. Fortunately, the skills that Freddie learned while he was in the Human dimension would leave them in the hands of not only a capable trainer, but someone who could turn them all into unstoppable killing machines.

Exploration is the third book in the Unseen Things series.