Chief O'Brien's Tragic Star Trek Timeline Explained

Senior Chief Petty Officer Miles O'Brien has led a storied life. He joined Starfleet at 17 years old, and by the time he settled down to teach engineering to cadets who outranked him the second they graduated, he'd served for 30 years. This jack-of-all-trades and certified transporter wizard can beam a radioactive MacGuffin through an ion storm in the middle of a swirly blue temporal distortion, keep a mishmash of Federation, Cardassian, and Bajoran technology running for seven seasons, and is an expert in starship combat, to boot. O'Brien doesn't need to be an officer to command respect.

However, O'Brien's rise from random bridge guy to main cast member wasn't all a shiny Galaxy-class ride set to heroic music. Star Trek loves to torture its engineers, after all, and our mild-mannered transporter chief has a biography that would make a Vulcan weep. Get the violins ready because we're about to dive into Chief O'Brien's tragic Star Trek timeline.

Chief O'Brien saw the horrors of war early on

O'Brien served aboard the USS Rutledge early in his career, when Starfleet was embroiled in the Federation-Cardassian War. During the conflict, the Cardassians came to believe that the Federation had established a military base on Setlik III, and they set out to destroy it. According to Memory Alpha, all they found was a civilian colony, but they attacked anyway, killing most of the colonists.

The Rutledge was the first Federation ship to arrive, leaving O'Brien to witness the bloody aftermath firsthand as the crew worked to rescue the remaining survivors amid Cardassian patrols. O'Brien saved 13 people by repairing a field transporter and beaming everyone away, but he truly distinguished himself when he led a group of two dozen against a regiment of Cardassians, an offensive which would change him forever. As he was protecting a group of civilians, two Cardassians ambushed O'Brien. He managed to knock one out, but he had to shoot the other ... with a phaser he didn't know was set to maximum.

O'Brien had never killed anyone before and was haunted by the incident for years to come. He was decorated for his valor in the colony and became known as the "hero of Setlik III," but he didn't relish the title, merely tolerating it. O'Brien came to resent Cardassians and would later recount that he hated the person he became after the massacre.

He had to face down his former captain

By the time of the Next Generation episode "The Wounded," the Federation and the Cardassians have signed a peace treaty, and a newly married O'Brien is serving on the Enterprise. The transporter chief's honeymoon gets tossed on its head, however, when he learns that Captain Benjamin Maxwell, his commanding officer during the war, has gone rogue and is attacking and destroying Cardassian ships. The Enterprise is tasked with entering Cardassian space and finding Maxwell's ship, the Phoenix, and bringing it home, a mission tailor-made to dredge up painful memories.

Maxwell's wife and children were killed in the Setlik III massacre, so it doesn't take long for accusations of revenge to fly. O'Brien, however, refuses to believe that his former captain doesn't have a good reason for what he's doing, and when the Enterprise crew finally catches up with Maxwell, the captain claims that the Cardassians are preparing to start another war. Captain Picard, however, is there to stop Maxwell from kicking off a conflict and orders the rogue officer to follow the Enterprise back to Federation space.

En route, Maxwell suddenly takes the Phoenix off toward another Cardassian ship, telling Picard that he'll destroy it if the Enterprise crew doesn't board it. In a bid to keep the two captains from trading photon torpedoes, O'Brien pulls some transporter magic and beams onto the Phoenix through its shields. There, he finally manages to talk Maxwell, who'd already killed more than 600 Cardassians, into surrendering.

Chief O'Brien took his own family hostage while possessed

O'Brien leads a generally happy life on the Enterprise, but he wouldn't be O'Brien if something bad didn't happen to him every now and then. In the TNG episode "Power Play," he's called upon for more transporter voodoo, in this case to beam a stranded away team up from a stormy planet. He succeeds in doing so ... but gets possessed, along with Data and Troi, by imprisoned alien lifeforms hoping to free their comrades.

The aliens are quite intent on moving the Enterprise into position to rescue their buddies, but they're not very patient and try to take over when they don't get what they want. They end up in Ten-Forward, the Enterprise's fancy space pub, where they take hostages, including O'Brien's wife, Keiko, and his newborn daughter, Molly.

After the Enterprise has moved to their desired location, the aliens each take a hostage (with O'Brien choosing Keiko) to a cargo bay, where the chief's transporter knowledge will be used to beam the rest of the prisoners on board. They're ultimately foiled, and it's revealed at the end of the episode that O'Brien was conscious the entire time he was possessed but was unable to do anything as he terrorized his own wife and daughter.

He almost succumbed to a biological weapon

O'Brien receives the promotion of his life after five years aboard the Enterprise. He goes from being the "beam me up" guy to the chief of operations of Deep Space Nine, the Federation's newest secondhand outpost. Of course, taking an everyman like O'Brien and making him the chief engineer in a Star Trek series is like dressing someone in sheet metal and having him run through a thunderstorm carrying a steel pole. Case in point: the DS9 episode "Armageddon Game."

In this outing, O'Brien and Dr. Bashir are helping two alien races, the Kelleruns and the T'Lani, destroy their stocks of biological weapons, along with all knowledge on how to create them. Neither of them were informed that this process includes killing everyone who helped to dispose of the weapons, leaving the duo quite confused when soldiers storm in and kill all the extras just as the last batch is being eradicated. O'Brien gets gassed by a bioweapon in the mayhem, but he and Bashir escape, leaving the two to sneak and fight their way to freedom as more soldiers hunt them, all while O'Brien gets sicker and sicker. Eventually cornered, Bashir and a nearly dead O'Brien end up facing an impromptu firing squad just before Sisko swoops in to save the day.

O'Brien was kidnapped and replaced by a duplicate

In literally the next episode after almost dying from an alien bioweapon, our beleaguered hero gets kidnapped. In "Whispers," O'Brien is helping the Paradans — who've been locked in a civil war for several years — prepare for peace talks, but then the Paradan government takes him and replaces him with a replicant. This copy has all of O'Brien's knowledge and memories and doesn't know what he is ... but he's also programmed to assassinate the rebels' diplomatic delegation. The Paradan rebels, however, are wise to the government's plan and warn Deep Space Nine before Fake O'Brien returns.

When the replicant gets "home," things aren't right. No one seems to trust him, he's kept from working on anything pertaining to the peace conference, and he realizes that he's being surveilled. He concludes he's run afoul of some massive conspiracy once Sisko and Kira try to arrest him, after which the replicant escapes.

O'Brien's duplicate ends up making his way back to Parada II, where he finds Sisko and Kira meeting with the rebels, but just as he thinks he's about to stop whatever they're plotting, he gets shot. That's when it's revealed that Sisko and Kira were there to pick up the real O'Brien, who now gets to watch himself die. The replicant's last words to his real counterpart are "Keiko ... tell her I love ..." Cheerful.

This Star Trek hero was framed by the Cardassians

Chief O'Brien takes a much-needed vacation in the DS9 episode "Tribunal" ... or at least he tries to. Everything is squared away for his absence from the station, and he even crosses paths with an old friend from the Rutledge, Raymond Boone, on his way to his shuttle. But then, as he and Keiko are en route to their destination, the Cardassians show up to arrest O'Brien, stunning him in front of his wife and carting him off.

On Cardassia, O'Brien is stripped naked, has a molar pulled from his mouth, and is repeatedly prompted to confess to charges he hasn't even heard. Eventually, O'Brien learns that he's been accused of smuggling weapons to the Maquis, Federation rebels who remain hostile to the Cardassians despite the peace treaty, and that the Cardassians who arrested him found photon torpedoes in his runabout's cargo bay.

O'Brien's execution is already scheduled, and the trial is a mere formality. He's just been declared guilty when Sisko enters the courtroom with O'Brien's old buddy Boone, except it isn't Boone. The real Boone was killed years earlier and replaced by a surgically altered Cardassian spy, who recorded O'Brien's voice when they "bumped into each other" and used it to steal the photon torpedoes and frame him, all part of a Cardassian ploy to discredit the Federation and increase their own negotiating clout. O'Brien, with a dead friend to mourn, is released.

O'Brien died (but kept on serving)

For most people, watching themself die would be a life-changing, traumatic experience. For O'Brien, it's Tuesday. In "Visionary," the chief finds himself briefly time-jumping a few hours into his future. While Dax and Dr. Bashir work to figure out the cause, a few more time shifts ensue, which give O'Brien a chance to do things like help himself in a Klingon bar fight and witness and subsequently prevent his own assassination, until a jump lands him in the morgue, standing over his own corpse. Luckily, Dr. Bashir is there to tell the chief that his autopsy revealed previously undetected damage to his nervous system due to the time shifts, information which O'Brien can relay once he shifts back.

Everything's going to be okay ... until O'Brien jumps forward one last time and finds himself piloting a shuttle full of evacuees away from Deep Space Nine as it explodes. To save the station, Bashir fashions a device that blasts O'Brien with radiation and sends him back to the future, a bit before DS9 blows. O'Brien wakes his future self up, and the two quickly figure out why the station blew when a Romulan Warbird decloaks and attacks. Dying from the radiation, O'Brien gives Future O'Brien the device so the latter can go back, warn everyone, and save the day.

He was given 20 years of prison memories

The universe's next gut punch comes in the form of the DS9 episode "Hard Time," in which O'Brien once again finds himself arrested, this time by the Argrathi. The chief is wrongfully convicted of espionage, and his captors have a very efficient correctional system. They implant the memory of a 20-year prison sentence into O'Brien's mind before the rest of the DS9 crew even knows what happened. In real life, only a few hours have passed, but as far as O'Brien is concerned, he's just spent two decades growing old and gray in a dark cell. He had one friend while incarcerated, his cellmate Ee'char, but near the end of his sentence, after the years had frayed his mind, O'Brien killed his friend for hoarding food, only to realize that Ee'char had been saving it for both of them.

And then he's suddenly back at DS9 with 20 years of unremovable prison memories. O'Brien tries to adjust but understandably can't get over what happened. He becomes ever more irritable and violent before finally almost hitting his daughter. After this, he runs off to a cargo bay, finds a weapons locker, and takes out a phaser, ready to commit suicide. Thankfully, Bashir talks him down.

O'Brien lost another friend

As detailed by Memory Alpha, during his time on Deep Space Nine, O'Brien becomes good friends with another crewman, Enrique Muniz. Sadly, this friendship doesn't last long. In "The Ship," Sisko, Dax, Worf, and O'Brien are surveying an alien planet, and they find a crashed Jem'Hadar vessel. With the main cast members are several other personnel, including Muniz, so you can probably guess where this is going. Another group of Jem'Hadar soon show up and destroy the DS9 crew's runabout, and our heroes are left holed up in the crashed Dominion ship.

During a firefight, Muniz receives a minor wound, which isn't enough to stop him from saving O'Brien from an infiltrating Jem'Hadar soldier. Muniz's wound won't stop bleeding, though, and it becomes apparent that the weapon that hit the crewman had poisoned him with some sort of anticoagulant. As O'Brien watches helplessly, his friend's condition deteriorates, with Muniz beginning to hallucinate that he's a child again, visiting a carnival with his dad. By the time the Defiant arrives to rescue O'Brien and the others, poor Muniz has died.

He just can't catch a break with Cardassians

Chief O'Brien simply can't catch a break when it comes to Cardassians, as seen in the episode "Empok Nor." O'Brien, Nog, and four Starfleet crewmen are sent to the eponymous abandoned space station to salvage parts. Along for the ride is DS9's resident tailor/spy Garak, who's there to disarm booby traps. The party's presence, however, awakens two Cardassian soldiers — left to guard Empok Nor — from stasis. They've been shot full of some serious mind-altering drugs, and they waste little time destroying the intruders' ship and killing two crewmen.

Garak, a clothier with no shortage of deadly skills, goes after the soldiers while the rest try to contact DS9. He kills one but is exposed to the drug. The other soldier takes out a third crewman and is about to kill the fourth when Garak dispatches him as well ... right before slaying the final crewman himself.

Garak proceeds to go full supervillain, taking Nog hostage and taunting O'Brien about the Setlik III massacre before O'Brien agrees to fight the Cardassian hand-to-hand on the station's promenade, where Garak has hung the bodies of the dead crewmen. Garak proceeds to beat the Starfleet out of O'Brien, but the chief manages to stun him with a strategically set-down tricorder rigged to explode. O'Brien, despite presumably acquiring a whole new pile of Cardassian-based PTSD triggers, later agrees to testify that Garak wasn't responsible for his drug-fueled rampage.

O'Brien had to betray a friend

O'Brien's résumé is further expanded in the DS9 episode "Honor Among Thieves," in which he's recruited by Starfleet Intelligence to infiltrate the Orion Syndicate, the biggest organized crime outfit in the Alpha Quadrant, to learn the identity of a mole the Syndicate has in Starfleet. Posing as a down-on-his-luck engineer named "Connelly," O'Brien utilizes his space handyman skills to earn the trust of a few Syndicate operatives, including Liam Bilby, for whom he does several jobs.

Things become more ominous when O'Brien is asked to repair several Klingon disruptors and subsequently witnesses the Syndicate meeting with a representative of the Dominion. At this point, O'Brien's assignment changes to finding out what's going down, and he discovers that the Dominion wants the Syndicate to assassinate a Klingon ambassador in order to destabilize the Federation-Klingon alliance. O'Brien passes this information on to his handler, who immediately warns the ambassador, but there's a problem. A genuine friendship has formed between O'Brien and Bilby, who's supposed to carry out the assassination and is now walking into certain death.

O'Brien visits Bilby, reveals his true identity, and warns him that the Klingons know he's coming. He urges his shocked friend to turn himself in or go into hiding, but Bilby chooses to go through with the assassination attempt and die so that the Syndicate will look after his family rather than kill them.

O'Brien nearly lost his daughter in Star Trek: Deep Space Nine

It's a good thing O'Brien's a workaholic because his days off are clearly cursed. In "Time's Orphan," he, Keiko, Molly, and his baby son, Kirayoshi, are enjoying a picnic on Golana, and everything's good until they hear Molly scream. She's wandered into a nearby cave, and O'Brien finds her hanging from the edge of a cliff, dangling over an alien time travel device. Molly falls before her father can save her, and then the portal deactivates. O'Brien and a science team get the time portal running again and beam Molly out, but they're met by a feral teenager, not an eight-year-old. Molly has been stuck in the past for ten years.

On Deep Space Nine, Molly has an understandably difficult time adjusting. Slowly, she makes progress, eventually uttering the words "mommy" and "daddy," but things take a turn for the worst when Molly freaks out and assaults several people in Quark's bar. Not wanting to see their daughter institutionalized, the O'Briens make a heart-wrenching decision — to send her back through the portal and then destroy it to keep her safe. After a last tearful goodbye, Molly tells her parents she loves them. On the other side, though, she finds herself back at the same point in time she was originally sent to when she was eight, and she sends her younger self back through the portal to her parents, an act which erases teenage Molly from existence.