4X01 - AUTHORIZED PERSONNEL ONLY - PART. After a second, he moves toward Vaughn again. Chase shows Sydney into a meeting room. End flashback. In Virginia. Man: Is isotope. No one deals with Vadik directly. Once she's the only one left, she walks to the end and down a set of stairs that leads to a door that has a dingy sign on it that says No Entry - Authorized Personnel Only. Sounds and lights indicate she is on a train. Sydney: Open it.
Plan: A: The fourth season; Q: What season of American Idol opens with a flashback from a scene of Sydney in hand-to-hand combat on a moving train? A: Sydney; Q: Who is on a mission to recover an isotope with a fantastic name? A: Vaughn; Q: Who did Sydney reconcile with after their brush with death? Summary: The fourth season opens with a flashback from a scene of Sydney in hand-to-hand combat on a moving train. We learn that she is on a mission to recover an isotope with a fantastic name. Sydney and Vaughn reconcile passionately after their brush with death. The plot leads directly into a second hour titled Authorized Personnel Only: Part 2.