The return of Star Trek: Deep Space Nine‘s Breen sets up a dark future timeline for the crew of Star Trek: Discovery. The Breen Imperium is one of the biggest threats to the peace and stability of the Federation in Discovery‘s 32nd century, proving that their defeat during DS9‘s Dominion War did nothing to suppress their hostile urges. Discovery season 5, episode 4, “Face the Strange”, written by Sean Cochran, and directed by Lee Rose, reveals that the Breen are potential buyers for the Progenitors’ technology, a prize that could have devastating consequences for the future of the Star Trek universe.

In Star Trek: Discovery season 5, episode 4, “Face the Strange”, Captain Michael Burnham (Sonequa Martin-Green) and Commander Rayner (Callum Keith Rennie) are thrown between past, present, and future by a Krenim time bug. Over the course of their travels in time, they arrive in a dark future timeline where the Breen used the Progenitors’ technology to destroy the USS Discovery and the entire Federation. As well as answering the mystery about the timeline of Star Trek: Short Treks‘ “Calypso”, this dark alternate future acts as a warning to Burnham and Rayner about what will happen if they let the Progenitors’ technology fall into the wrong hands.

Who Were The Breen In Star Trek: Deep Space Nine?

The Breen nearly changed the course of the Dominion War.

The Breen were first mentioned in Star Trek: The Next Generation season 5, episode 11, “Hero Worship”, when they were suspected of attacking the SS Vico. However, the Breen wouldn’t appear on screen until Star Trek: Deep Space Nine season 4, episode 5, “Indiscretion”, in which Gul Dukat (Marc Alaimo) and Major Kira Nerys (Nana Visitor) infiltrate one of their labor camps. “Indiscretion” established that the Breen wore refrigeration suits, presumably to maintain their body temperatures on hot worlds like Dozaria. The Breen were also an incredibly warlike species, which made them crucial allies of the Dominion following their defeat in the First Battle of the Chin’toka System.

The Breen and the Dominion’s negotiations led to an alliance that lasted until the end of Star Trek: Deep Space Nine. The Breen had superior technology, including an energy-dampening weapon that could disable the Federation Alliance’s ships, including the USS Defiant. The Breen’s energy dissipater played a crucial role in the Second Battle of the Chin’toka System, severely weakening the Federation Alliance’s armada and their morale. The Breen planned to roll out their energy dampening weapon across the entire Dominion fleet, but were foiled by a covert mission led by Colonel Kira Nerys, Elim Garak (Andrew Robinson) and Constable Odo (Rene Auberjonois).

In tandem with Kira’s mission, the Federation Alliance used a series of countermeasures against the Breen’s weapon. These measures helped the Federation Alliance to turn the tide against the Dominion, launching a final assault on Cardassia Prime and eventually winning the war. Breen representatives were present at the historic signing of the Treaty of Bajor, putting an end to their war against the Federation. However, 800 years after the end of Star Trek: Deep Space Nine, it appears that the Breen are just as big a threat in Star Trek: Discovery season 5.

DS9’s Breen Create Star Trek: Discovery’s Darkest Future Timeline

“But the outcome you feared came to pass. The Progenitor’s technology fell into the wrong hands.” – Zora

In the alternate timeline where Burnham and Rayner didn’t destroy the Krenim chronophage in time, Moll (Eve Harlow) and L’ak (Elias Toufexis) handed the Progenitors’ technology to the Breen. The Breen used the incredibly powerful Progenitors’ technology to launch a devastating attack against the Federation. Standing aboard a devastated USS Discovery, Burnham and Rayner look out at the ravaged remains of Federation Headquarters. After a false start during the Dominion War, the Breen will finally get to destroy the Federation once and for all unless Burnham and Rayner can stop them acquiring the Progenitors’ technology.

As Commander Paul Stamets (Anthony Rapp) surmised earlier in Star Trek: Discovery season 5, the Progenitors’ technology can both create life and destroy it. In the hands of the Breen, it will be used not to save lives, but to take them. It’s unclear exactly what the destructive capabilities of the Progenitors’ technology are. However, the fact that the USS Discovery is completely empty of organic life or material suggests that it could have the power to completely break down the building blocks of humanoid life in the galaxy. With such a devastating weapon in their arsenal, the Breen could rule the entire cosmos without opposition.

Star Trek: Discovery’s Future Breen Can Finish What They Started On DS9

“To launch an attack against Starfleet Headquarters… even my people never attempted that.” – General Martok

Star Trek: Discovery‘s dark future timeline isn’t the first time that the Breen have attacked Federation Headquarters. The Breen’s first act after allying themselves with the Dominion was to launch a devastating attack on Earth in Star Trek: Deep Space Nine season 7, episode 20, “The Changing Face of Evil”. The Breen’s attack on Earth in DS9 seriously damaged Federation Headquarters and took a huge chunk out of San Francisco’s iconic Golden Gate Bridge. Starfleet fought off the attack, destroying the Breen interceptors, but the attack still had the desired effect of seriously damaging the morale of the Federation-Alliance.

The Breen’s attack in Star Trek: Deep Space Nine caused heavy civilian casualties and an unknown number of military losses. However, it was as much a psychological attack as it was a physical one, proving to the Federation that they couldn’t even protect their homefront during the Dominion War. The Breen in the 32nd century seem not to care about getting into the heads of their enemies and are instead focused on their total destruction. They may have struck a powerful blow against the Federation 800 years ago, but in Star Trek: Discovery‘s 32nd century, the Breen can finish the job with the help of the Progenitors’ technology.