Writer: Haden Blackman
Watching the holo recordings in the Jedi Temple, Vader learns that during the Clone Wars, the Jedi kept the most dangerous prisoners in a secret location called the Prism (located near the Sixth Moon of Diab). After the war was over, they would be brought to trial, but with the Jedi now dead and scattered, that never happened.
On their way to the prison with the Emperor and Trachta, Trachta tells Tohm that he was disfigured by a bomb on Noctralis, thrown at him by a Jedi Padawan who had defected to Count Dooku.
Tohm says he was disfigured when Confederates blew up his family's Tibanna gas processing plant. He was the only survivor from his family.
Meanwhile, Headmaster Gentis contacts the other officers currently off-world, including Grand Moff Tarkin, and tells them that he has saved the Emperor's life and put down the rebellion, but that Vader and Trachta are missing, thus framing them for the rebellion.
Tarkin says he will arrive on Coruscant soon and will take command.
The Prism was built during the Great Schism. It only requires one Jedi and one hundred security droids. No transmission are allowed in or out. That's why the Jedi warden did not know that the Jedi had nearly been wiped out.
Vader kills her and destroys the droids. They then discover that the prison is holding two hundred and eight prisoners, half of whom were personally arrested by Anakin Skywalker.
Trachta sees that one of the prisoners is the Jedi Padawan who disfigured him. He enters his cell and beats him to death.