In this episode, Quark and Rom ferry Nog to Starfleet Academy in Quark's personal shuttle. During the trip, a temporal anomaly sends them to 1947 Earth where they are held prisoner in Roswell, New Mexico.
Quark receives a shuttle that his cousin Gaila has been promising him for years. He christens it Quark's Treasure and for its maiden voyage takes his brother Rom and nephew Nog to Earth, where Nog has been accepted to Starfleet Academy in San Francisco. Quark also intends to make the trip financially profitable by smuggling a load of illicit kemocite explosive to Orion on the return voyage.
As the ship nears Earth, Rom finds that due to sabotage by Gaila they are unable to drop out of warp. However, by detonating part of the unstable kemocite "shipment" to create an explosion they can drop out of warp. Unfortunately, in doing so the ship and crew are thrown back in time to July 1947 and crash land near Roswell, New Mexico. The Ferengi awake on a U.S. military base, where the Americans believe them to be Martians. After Rom repairs their malfunctioning universal translators hidden in their ear canals, Quark begins negotiations with the humans, whom he considers backward and gullible, to sell advanced technology from the future. He brags to Rom and Nog in private that "within a year we'll be running this planet," and dreams of cultivating a vast Ferengi economic empire.
Unknown to the Ferengi, however, Constable Odo had stowed away aboard the shuttle with them and as a result was also thrown back in time. Using his shape shifter abilities, Odo is able to move about the base locating and repairing their spacecraft. He then appears as a German Shepherd Guard Dog in the room where the Ferengi are being held, and morphs into his normal form, telling Quark that he knew about the kemocite smuggling, and that they must try to preserve the timeline and not alter Earth history. Quark, Rom, and Nog then escape from custody with the help of an Army nurse and her college professor boyfriend who has been brought to the base to try to establish dialogue with the aliens.
By harnessing the energy of an atomic bomb test scheduled for that morning, Rom is able to use the remaining kemocite to cause a temporal rift which returns them to their proper time. After dropping off Nog at Starfleet Academy, Quark has to sell the damaged spacecraft for salvage and he, Odo, and Rom return to Deep Space Nine. As the episode ends Odo is seen strong arming Quark off to a holding cell to face charges of smuggling contraband.
The producers requested a "Megan Gallagher type" for one of the roles in the episode. Upon hearing about this, Gallagher's agent contacted them and said that Gallagher might be able to do it herself. Following this she was offered the part in the episode. She had previously appeared in the second season episode "Invasive Procedures" and would later appear in the Star Trek: Voyager episode "Body and Soul".