The Sol Empire Volume 5 Genetic Engineering begins with Molly Parkinson now attending Soros University on Cass-C, close to the center of this half of the galaxy and the home of the Federation of Planets, far from Earth. She and Dirk Bennet's arms are regrowing when Dirk discovers a fruitful clue to the location of one of the five rogue human-form robots that's killed her first husband, Ted, and others. Accompanied by her long-time security guard, Bishop, one of the five human-form robots that had been programmed with the robotic laws, they follow Dirk's new clue.
As they show up at the store that's been purchasing fifty-three top-of-the-line positronic brains, the rogue robot and its two giant guards burst out, guns blazing. While Bishop's reactions are lightning fast saving her from three shots, one slug penetrates Molly's head and ought to have killed her. Bishop injects her with the Sixth Invaders' armless telepath Galactic Doll mutation agent, one which has saved her live several years ago. The Fetal Regeneration begins, mutating her back into her previous body form. The rogue robot escapes, despite being hit twice by Dirk's gunshots.
As she's recovering, the Intelligence Division orders them to leave the investigation to the ID people. Convalescing in her campus apartment, she discovers her maid is a bird-like person, the Vogelmenschen. Via Molly's telepathic skills, she learns the woman was once a human who was knocked out, kidnapped, mutated into this bird-like form, taught Federation Common, and sent to Soros U to work as a maid. In fact, Molly discovers hundreds of these Vogelmenschen are here, all with similar stories.
She vows to put a stop to this and believes Ashton Soros, who tells her he acquires them from ABC Shipping. She, Dirk, and Bishop ignore the ID threats to leave it alone and head there to investigate. Though they are alert for more clues about the rogue robot.
The top rulers of the Federation of Planets know about the Vogelmenschen and the huge genetic engineering project. They order the ID to pretend to investigate and keep tabs on Molly and Dirk. There ID agent follow Molly's group, but at the genetic engineering facility, two ID agents are discovered and mutated, too. Molly and Dirk uncover the massive genetic engineering operation and shut it down, with the help of the third agent. They discover the Third Invaders are behind this operation.
Before they can track this further, Molly and the ID agent are sent to Earth, Sol Empire to help stop an invasion of worms. They are successful, but discover the Third Invaders caused it, in part to prevent Sol deep space exploration ships from discovering and claiming another inhabited world that's in its industrial age. The Third Invaders colonized the world with a thousand mutated humans from Earth two millennia ago and want to prevent its discovery and incorporation into the Sol Empire.
Molly goes there and uncovers the truth, but when she returns to Chicago to report, the Sol Empire's top leaders have been killed. She steps in and takes over becoming the Empress of the Sol Empire.
Sol Empire has three governing bodies. The Senate on Brussels, Tau Ceti, makes the laws. The Office of President on Pylon, Epsilon Eridani enforces those laws and handles defense matters. The Senior Investigator and Senior Judge on Earth handles those matters and can veto any Senate law or any action taken by the President.