We meet Dr. Vaughn, creator of the DRN models including Dorian, and a later DRN that went bad - that is, is ready to coldly and ballistically kill people, other robots, anything that gets in her way on whatever mission. What we don't learn until the end is what was implied all along - that the bad robot was designed that way by Vaughn, either deliberately or unintentionally because he was embittered, but with the same murderous result. In any case, he's now more than willing to use her for his ends - which is to reestablish himself and reclaim his lost power as the leading robot creator - and with his escape "over the wall" at the end, we now have an arch villain on our hands in Almost Human.
The bad robot, though, is destroyed, as Dorian and Kennex get the better of her, and Kennex lands the fatal blow by wielding his synthetic leg for the kick. This serves as a good occasion for Kennex to tell Dorian that the prosthetic leg is growing on him.
Meanwhile, we get some good heart to heart between Dorian and Kennex, as Kennix assures Dorian that he's not at all like the bad robot, because he's unique and indeed was created earlier, when Vaughn was in a different state of mind. Kennex's acceptance of Dorian, and their growing friendship, is the one of the best continuing threads of this series.
And what's over that wall? Well, something horrible, but likely not as monstrous was what lurks on the other side in Game of Thrones. Still, in the future science fictional world of Almost Human, we can only assume that what resides beyond the wall must be worse than what we've seen inside Detroit so far. And since that's been pretty bad, what lies beyond it must be bad indeed. Which is why I'm looking forward to seeing it in due course.
See also: Almost Human debuts: A Review ... Almost Human 1.2: Sexbots ... Almost Human 1.3: Change of Face ... Almost Human 1.4: Almost Breaking Bad ... Almost Human 1.5: Clones and Holograms ...Almost Human 1.6: The Blackmarket Heart and Double Dorian ... Almost Human 1.7: Meets Criminal Minds ... Almost Human 1.8: Guided Bullets