A group of alien visitors are stuck in an airlock as O’Brien and crew work to try and free them. To pile on the work, a freighter captain demands O’Brien fix his ship before his shipment spoils. Just to make matters worse, Dax calls for him in the science lab. A screetching sound pierces the room… but it’s a simple fix – until the lights go out.

In Ops, Kira stares disbelievingly at the navigational computer… which is blinking on and off. It hasn’t worked reliably for three days she says. O’Brien sticks his head out from the floor after repairing it.

Next, it’s Sisko’s turn… as O’Brien leans on the console trying to take a break our Commander orders a beverage from the replicator only to get a nasty surprise… “Chief, I thought you were going to fix this!?” “You’re absolutley right, sir… can’t have the operations chief sitting about!” (Classic line, classic delivery.)

Inside a command level replicator, the Chief is working away while mumbling to himself – something about transferring to a cargo container… no people there! But, lurking in the depths is a mysterious looking device, which activates.

Meanwhile, Odo and Quark sit at his bar noting the lack of people… it’s all thanks to another broken replicator. The one sole customer complains about his stew, and begins to force feed it to the Ferengi, Odo intervenes and the customer walks away very unhappy.

Odo mentions the command level replicators are working perfectly, so after Odo leaves Quark hacks the system to find a vacant machine. Back in Ops, O’Brien gives Sisko a proper coffee, which is exactly what he was after. As O’Brien leaves to check on the environmental controls… he drops a few nonsensical words.

Meanwhile, on the promenade, Dax and Kira are walking along as the Trill is getting alot of attention… something she’s missed after 80 years as a male. They pass Quarks who invites them in to celebrate the fixed replicator, Kira rebuffs the advance and heads to Ops – where we find O’Brien struggling to stay awake then he starts speaking in only nonsense.

In the infirmary, Bashir can’t find anything wrong… and at a staff meeting Dax begins to speak gibberish too. Sisko orders a quarantine and everyone isolated to their quarters.

Quarks is still open though, and that unsatisfied customer is happily eating a new bowl of stew. On the second level, Jake is worried… and that freighter captain really wants to get underway. But Sisko says no.

In a habitat ring corridor, Quark breaks into a room and starts ordering from the replicator… but the trolley he’s pushing morphs into Odo. The Constable mentions that he poked a hole in Quarks story when he said that Rom fixed the replicator (obviously Rom is smarter then they give him credit for, by flying under the radar at this point!)

In Ops, Bashir, Sisko and Kira try to determine where the virus is coming from and how its affecting the whole station – thanks Quark! Bashir then discovers the virus is now airborn.

After an intense search they find the device causing all the problems… it builds the virus right into the replicated food. Sisko gets called to the infirmary where Jake has been struck down. A hospital ward has been established in crew quarters… but Bashir has more news – the virus is Bajoran in origin, it must’ve been created during construction of the station.

Kira begins her very quick search for the creator of the virus – who’s dead, that leads her to his death certificate which leads her to the signature of the witness. In the hospital ward, Jake and Dax lead a nurse to O’Brien who is burning up.

Sisko recruits Odo to Ops, as Kira demands a runabout to continue her conversation with the witness. Seeing he has no alternative, Sisko lets her go. After consoling his son, the freighter captain tries to leave… but the docking clamps are sealed and he’s fighting to break free.

On the runabout, Kira scans for Doctor Sermack who stands up and Kira beams him aboard. Back on the station, the freighter suffers severe damage… and Odo races down to the docking port to explode the clamps.

Doctor Sermack demands he be returned to his office, but Kira says she’s infected him so it aint gunna happen. With Sisko now aphasic too, Odo calls for help – only to have Quark respond. More of the awesome duology ensues as Odo saves the freighter captain and frees the ship.

In the Infirmary, rather quickly, Sermack develops the antidote and releases it. The day is saved.