Black Omega, a Starfury wing, encounters a transport ship in deep space and orders it to surrender. A pulse of energy from the ship completely destroys the Starfury wing. On Babylon Five, Catherine Sakai (Julia Nickson) and Commander Jeffrey Sinclair (Michael O’Hare) enjoy the morning in his quarters. She is preparing a survey for Universal Terraform and is just about to meet the representative. The same transport ship jumps to Babylon Five and docks there.

Telepath Talia Winters (Andrea Thompson) rides the lift with Security Chief Garibaldi (Jerry Doyle) and the representative from Universal Terraform (Kevin Page) on his way to meet Catherine. He asks Talia what it’s like to be a telepath. She explains that strong emotions are hard to block, and then elbows Garibaldi in the gut. Talia mediates at Catherine’s meeting, about Quantium 40’s presence on Sigma 957, but its location in disputed space requires consultation with Narn ambassador G’Kar.

A pair of Psi Cops enter the station and telepathically request a meeting with Sinclair. He insists they speak verbally. They are Alfred Bester (Walter Koenig) and Ms. Kelsey (Felicity Waterman) and are looking for a rogue telepath they believe is on the station. They want to meet with Talia Winters and the senior staff because this individual is a threat to Earthforce. Meanwhile, the rogue they seek rents a room, suddenly flinches, and the room shakes.

Bester explains it is Jason Ironheart (William Allen Young), a former instructor at the Psi Corps Academy, who taught Talia Winters. He was assigned to a classified operation with Earthforce Special Intelligence but has gone rogue and is selling classified information. Winters does not believe it and the Psi Cops subject her to a deep scan, which upsets both Winters and Sinclair, to see if she has had contact with Ironheart. She has not. After she is dismissed, Ironheart approaches her in the corridor. She attempts to walk away, but he pleads for help.

G’Kar refuses permission for Catherine Sakai to approach Sigma 957 and she confronts him in the marketplace. He insists that Sigma 957 is a dangerous place. Ironheart explains to Talia that the experiment he volunteered for was to develop stronger telepaths. It succeeded too well, and he read in the experimenters’ minds that it was actually to develop stable telekinetics. He had to flee the Psi Corps.

Garibaldi has a lead on Ironheart. He wants the Psi Cops off the station. Bester walks in, arrogantly chiding Garibaldi for his thoughts. Sakai leaves on a ship for Sigma 957 and G’Kar calls Narn Military Headquarters requesting Frazi class heavy fighters sent to the planet. Ironheart explains that Psi Corps wants telekinetics as silent assassins. He suddenly lurches in pain and tears the room to pieces. The whole station feels what Kelsey calls a mind-quake.

Garibaldi informs Sinclair that the epicenter of the disturbance is behind an impenetrable energy field encompassing Blue 16. Behind this, Ironheart tries to calm himself. Sakai exits hyperspace for Sigma 957. Bester says Ironheart proved unstable, killed the head researcher, and fled the facility. His powers are increasing exponentially. Bester wants to prevent alien governments from capturing him. Kelsey has a safe word that will put Ironheart to sleep if spoken in line of sight.

Talia approaches the energy field and calls to Ironheart. He opens to her. He is distraught among the wreckage. He warns her that Psi Corps is manipulating Earthgov, and he is becoming something else. Talia informs Sinclair. He agrees to come with her to see Ironheart. In the core-shuttle on the way, she admits that she and Ironheart were lovers at the Academy. At Sigma 957, Sakai scans the planet. A strange, huge ship appears and disappears. Her ship fails and she is trapped in the gravity well. A pair of Narn fighters dispatched by G’Kar appear to escort her to safety.

Sinclair meets with Ironheart, who says that Psi Corps is out for total control and pleads to finish his transformation. Sinclair orders Garibaldi to clear a path to a docking bay. Bester and Kelsey waylay them, and she hits Ironheart with the safe word, causing him to lose control. Sinclair knocks Bester down, Kelsey draws a gun, and Ironheart vaporizes her with his mind. Bester recovers and shoots Ironheart, who knocks him out with an energy blast. Ironheart leaves in his ship and a being of pure energy announces he has “become”. He gives Talia Winters a parting gift in a bolt of energy.

Sinclair and Garibaldi confer with Bester, telling him that an accident will soon erase the data they show him. Bester must cover this up on Earth or Sinclair will reveal how Bester endangered lives and got Kelsey killed. Bester leaves, saying, “Be seeing you.” Sinclair tells Garibaldi that without evidence it’s all just a paranoid conspiracy theory. In her quarters, Talia Winters moves objects with her mind. Catherine returns and thanks G’Kar for his help. She asks him about the alien ship at Sigma 957. He says they are ancient beings who are hardly even aware of younger races and could easily step on them like ants.

Psi Cop Alfred Bester is named after the author of The Demolished Man, a novel about a murder in a society run by telepathic police. Walter Koenig, of course, played Chekov in the Star Trek Original Series and the films based on it. He was not the only Babylon Five actor to have played roles in Star Trek. Andreas Katsulas and Bill Mumy were also featured. Claudia Christian auditioned for the role of Seven of Nine. Walter Koenig kept his left hand clenched in a fist the whole time, as if Bester was crippled. His good-bye, “Be seeing you,” is from the 1967 British series The Prisoner, with Patrick McGoohan. Ivanova asks the Psi Cops, “Who watches the watchers?” which comes from the Roman Poet Juvenal via the Watchman comics, some of which J. Michael Straczynski wrote. G’Kar’s line, “No one here is exactly what he appears to be,” becomes a featured phrase in Season Five.

Catherine’s ship is an Earth Alliance shuttle with an exterior skeleton. The Starfury fighters were the first spacecraft on TV to fly according to Newtonian principles in a vacuum, instead of maneuvering like aircraft in an atmosphere. Babylon Five’s defense fighters appear in four squadrons: Alpha, Beta, Delta, and Zeta. Beta Squadron never appeared in the series. The Omega-class destroyers of the Earth Alliance were based on the Russian ship Leonov in the movie 2010. The mysterious ship at Sigma 957 is that of The First Ones, related to the Vorlons. Kosh has a ship designed like a clove of garlic. The vessels of the Shadows (which feature later in the series) look like black spiders.

Quantum 40 is valuable because it is used in constructing jump gates. The station’s computer is of Centauri design with a Centauri AI. When G’Kar orders the fighters, he identifies himself as Third Circle, which is his social class. Narn society is concentric in nature, the inner First Circle is the Royal Family, outside of that is the Second Circle or religious class, and outside of that is the Third Circle of high-ranking civil servants.