A transport ship docks with the station.
Sinclair sits down to eat with Garibaldi. Delenn and Lennier interrupt them; there is a distinguished guest coming aboard, Delenn says, and Sinclair should greet him.
In Downbelow, a crime boss named Deuce asks another man, Jinxo, to provide him with the locations of secret passages in the station. Jinxo replies that while he did help build Babylon 5, he was mostly involved in big structural construction and can't provide that information. Deuce insists that he can - or else. He gestures to another part of the room, where a woman is tied down in a chair. Her name, Deuce says, is Mirriam Runningdear, and she agreed to testify against him. Now she'll pay the price. He beckons to something in the shadows. A Vorlon encounter suit comes forward. The front panel opens and a tentacle extends out, attaching to Runningdear's forehead. Deuce tells Jinxo to have the plans, or 50,000 credits, within 300 cycles, before Ambassador Kosh gets hungry again.
In a courtroom somewhere on the station, an ombudsman listens to testimony from a man who's suing aliens for abducting his great-grandfather.
Sinclair, Garibaldi, Delenn and Lennier greet a man named Aldous Gajic. He says he didn't notify Sinclair of his arrival because his mission is not Earth-related. He reveals that he's looking for the Holy Grail, and, as his order has looked everywhere on Earth, he has come to the station to talk to the alien ambassadors about its possible whereabouts. Sinclair, incredulous, excuses himself.
Delenn catches up with Sinclair and asks why he holds Gajic in such contempt. Sinclair explains that the Grail is just a legend, but Delenn counters that that doesn't matter; Gajic is a holy man, a "true seeker," devoting his life to a search for enlightenment and the bettering of his race. "I wish him luck," Sinclair says. "He's probably the only true seeker we have."
"Then perhaps you do not know yourself as well as you believe," Delenn comments, and walks off. Sinclair gets a call from Dr. Franklin; there's another brainwipe victim.
Gajic is changing money when Jinxo walks by and picks his pocket. Garibaldi is watching and grabs Jinxo before he's gone twenty feet. Gajic wants to let Jinxo go, but Garibaldi says that Gajic is a witness and insists that he testify.
In medlab, Franklin and Sinclair look at Mirriam Runningdear, who lies unconscious. Franklin says her brain has been wiped clean, synapses fused, leaving it barely able to keep her autonomic functions going. She'll live, but she'll have to start all over again, as her life experience is gone. Garibaldi is furious that his sole witness against Deuce has been "reduced to a rutabaga" and asks Sinclair for permission to sweep through Downbelow with his men. Sinclair tells him to wait until there's proof that the brainwipe is in fact connected to Deuce.
The ombudsman sentences Jinxo (whose real name is Thomas.) He is barred from the station for five years. Jinxo objects strongly: "I can't leave the station, or it's the end of the station - and every man, woman and alien on the station!" Gajic speaks with the ombudsman and convinces him to remand Jinxo to his custody. As Jinxo leaves, he's pulled aside by Deuce, who reminds him that he has only 240 cycles left.
Next, the ombudsman reads the charges against Deuce, who pleads innocence. Garibaldi tells the ombudsman about Runningdear's condition. Unfortunately, without her testimony, there isn't enough evidence; the ombudsman dismisses the case against Deuce.
Gajic takes Jinxo to his quarters and asks why he thinks he can't leave the station. Jinxo answers that it's the "Babylon curse" - if he leaves, the station will blow up or disappear or something else will happen. When Gajic asks how he got the curse, Jinxo answers, "Don't you get it? I don't have the curse. I am the curse."
Jinxo explains that he was too young to fight in the war, so when he had the opportunity to work on the original Babylon station, he jumped at the chance. Three months into it, he went on leave, and the station's infrastructure collapsed, the result of sabotage. The same thing happened to Babylon 2. Babylon 3 blew up while he was away, and he got the nickname "Jinxo." When Babylon 4 was being built, Jinxo stayed the entire time, until it was completely finished. He thought the curse was gone. "But as I was leaving on the shuttle, I looked back, and the station just sort of wrinkled. Twisted like putty. And then it just... disappeared."
Gajic suggests that Jinxo should have been nicknamed Lucky - he managed to escape death four times.
Franklin and Ivanova suggest a possible cause of the brainwipes: a creature from an off-limits world in Centauri space called a na'ka'leen feeder.
Sinclair asks Londo about the feeders; Londo says they're very dangerous creatures. The Centauri lost an entire colony to them. When Sinclair lets slip that there may be one on the station, Londo makes a beeline for his quarters, and suggests Sinclair does the same.
Gajic and Jinxo visit Delenn, who says the Minbari don't have the Grail, nor had they heard of it before Gajic asked them. Lennier says they searched their files very thoroughly. Delenn tells Gajic that she will have word sent to all Minbari outposts, and if one of them hears about the Grail, they will find Gajic and tell him. Jinxo is amazed; after the war, he figured, the Minbari wouldn't be eager to help a human. Lennier explains that there are two castes of Minbari: the warrior caste and the religious caste. "The warrior caste... would not understand," he says.
"So we will not tell them, and spare them the confusion," Delenn says.
"These two parts of your society. Do they ever agree on anything?" asks Gajic.
"Yes," says Delenn. "And when they do, it is a terrible thing. A terrible force, as recent events have shown. Let us hope that it never happens again in our lifetime."
In Downbelow, Kosh (or is it a feeder?) pleads with Deuce to bring him more food, older minds. The voice is high and tinny, not the usual melodic rumble of a Vorlon voice. Deuce orders a henchman to fetch Jinxo and the ombudsman.
Dr. Franklin tells Sinclair that using the file provided by Londo, he can confirm that Runningdear was indeed attacked by a na'ka'leen feeder. Sinclair tells Ivanova to run a check on every ship entering the station in the last ninety days. Garibaldi says he's going to track Jinxo down, as he saw Deuce and Jinxo talking at the trial.
Londo speaks with a Centauri government representative, trying to get the government to reinstate the quarantine on the feeders' world. Gajic and Jinxo are waiting to talk to him. Gajic asks about the Grail. Londo says he can search the Centauri-Earth trade files, but it will be very time-consuming and expensive. Vir interrupts and says he's already done it, in the interest of efficiency, prompting Londo to scold him. Gajic and Jinxo leave in a hurry.
Gajic tells Jinxo that if he finds it, he will use the Grail to heal. "Perhaps it has enough power to heal the entire human race," he says. Jinxo asks how he got started looking for the Grail.
Gajic did the accounts for a large Earth corporation, he says. He lived in a world of numbers, logical and clean. He and his family took a vacation on the Mars colony. An accident killed his family but left him alive. He mourned for a long time, and when he returned to work he found that the numbers didn't make sense. He began to wonder why he was spared. And then he met a man, the last of his kind, who told him he was a man of infinite promise and goodness. When the man died, he entrusted his legacy to Gajic. Now Gajic is the last of his kind. "The numbers add up again, Thomas," Gajic concludes. "The numbers do add up."
Deuce's men kidnap the ombudsman.
Two thugs try to capture Jinxo, but Gajic fights them off. Jinxo, panicing as he thinks of what Deuce will do now, asks if he can learn to fight like that. "You can learn whatever you like," Gajic says, "because you are a man of infinite promise and goodness." When Jinxo scoffs, Gajic points out that Jinxo is willing to stay on the station to protect its people, even at the risk of his own life.
The two of them go to visit Kosh. When Jinxo sees Kosh, he runs away, terrified, warning Gajic to stay away or Kosh will eat his mind.
Gajic catches up with Jinxo in Downbelow and convinces him to talk to Sinclair if he has information about the Vorlons. Deuce's men attack; Gajic fends them off long enough for Jinxo to escape, but is captured himself.
Ivanova reports to Sinclair that she hasn't had much luck figuring out which ship might have brought the feeder onboard. Garibaldi links in and tells Sinclair the ombudsman has been kidnapped. Sinclair leaves to see the scene of the crime for himself.
The ombudsman, strapped to the same chair Runningdear was, watches in horror as the feeder approaches in the Vorlon encounter suit. Deuce reassures him that if there's any pain, it won't last long. Deuce's men bring Gajic in.
Jinxo finds Sinclair in the hallway and tells him that Deuce is going to feed Gajic to the Vorlon. Sinclair goes with him and tells Garibaldi to follow his signal.
Gajic steps between the ombudsman and the feeder. The feeder moves to attack Gajic, but stops short, then withdraws its tentacle. Gajic speaks softly. "There is nothing in the dark. No fear, no pain. Only the light. Show yourself."
The feeder, resembling a cross between a squid and a jellyfish, steps out of the suit.
Garibaldi's men blast the door in and a firefight ensues. The feeder leaps up into the pipes crisscrossing the ceiling. As the firefight continues, it drops behind one of Garibaldi's people and strikes, then, more confident, approaches the ombudsman. Jinxo leaps out from his hiding place and unties the ombudsman's hands, but he doesn't notice Deuce taking aim at his back. Gajic does, and takes the shot. The feeder is blown to pieces by Garibaldi, Sinclair, and the security team.
Before Gajic dies, Jinxo promises to continue the search.
Sinclair visits Kosh and tells him Deuce was using an excellent replica of a Vorlon encounter suit so people would think he had the Vorlons on his side, making him appear more fearsome. "Why?" asks Kosh.
"No one knows exactly what you look like," Sinclair answers. "And that makes some people a little nervous."
"Good," Kosh replies.
Sinclair and Delenn see Gajic's body off. "It's hard," Sinclair says, "to spend your whole life looking for something and never find it."
"Are you speaking of Aldous, or someone else?" asks Delenn.
Sinclair looks at her for a moment. "Aldous," he finally answers.
"There you are wrong. He found what he was looking for. What we are all looking for. A reason."
"Everything, Commander. Everything."
Jinxo arrives just as the coffin is about to be loaded aboard the ship. Delenn gives him a crystal. "Put this on his grave, and crush it," she says. "It will glow every night for a hundred years. It is our way with all true seekers," she continues, with a meaningful glance at Sinclair.
"Good luck, Jinxo," says Garibaldi.
"Thomas," he answers. "My name is Thomas."
Sinclair, Ivanova, and Garibaldi are back in C&C, discussing the Babylon Curse, when Thomas' ship leaves the station. It enters the jumpgate. "No boom?" asks Sinclair. "No boom," answers Garibaldi.
"No boom today," Ivanova corrects them. "Boom tomorrow. There's always a boom tomorrow." Sinclair and Garibaldi shake their heads and leave.
"What?" Ivanova asks. "Look, someone's got to keep some damned perspective around here. One of these days... boom!"