As Enterprise ventures deep into the Expanse, the ship is rocked by inexplicable, destructive spatial anomalies that distort the laws of physics. The anomalies take most of the ship's primary systems off-line, leaving Enterprise without weapons or warp capabilities.
Meanwhile, Mayweather notices that there is a ship nearby, adrift in space. No bio-signs are detected, so Archer, Reed and several of the MACOs take a shuttlepod to the derelict ship in order to ascertain what happened to the aliens onboard. The alien crewmembers are all dead, their corpses floating through the air. Further study reveals that most of them died when life support ran out, but some of them were killed by particle weapons. Concerned that whoever attacked the alien ship could come after Enterprise, Archer orders Mayweather to resume course — the crew will have to make repairs on the move.
As Trip struggles to create a stable warp field, another vessel approaches Enterprise and a group of alien marauders beam onboard, stealing weapons, food and precious supplies. Trip, Reed and other crewmembers manage to fend them off, but one crewman is killed in the chaos. The aliens also leave behind one of their own, an individual named Orgoth. Phlox recognizes him as an Osaarian, a species not originally from the Expanse. Archer hopes to track the Osaarian ship and recover the stolen items, but the Osaarians have masked their ion trail. Archer, however, is determined to find them.
Hoping to glean more information, Archer confronts Orgoth, now imprisoned in the brig. Orgoth won't reveal much — he's more interested in observing Archer, and notes that the captain seems quite "civilized" and "moral," and that he must be new to the Expanse. Orgoth explains that his people were forced to resort to desperate measures because of the conditions in this perilous region of space. The Osaarians entered the Expanse as merchant ships looking for new trade routes. After the first wave of anomalies hit them, they wanted to return home, but were unable to because of the thermobaric clouds around the perimeter. One of the Osaarian ships was destroyed attempting to exit the Expanse — the other one turned to piracy. Orgoth adds that he doesn't see Archer as someone who is ready to kill or torture just yet. Archer claims that he's willing to do anything to find the Osaarian ship.
Using data recovered from the derelict ship, Enterprise is able to track the Osaarian vessel. As the crew follows the trail, they suddenly find themselves in the middle of a bizarre cloaking field, which wracks the ship with distortion waves. As they emerge on the other end of it, they find a large sphere constructed out of a single alloy. Archer and several crewmembers take a shuttlepod into the sphere and discover a series of habitat modules containing most of the goods stolen from Enterprise. The crew also finds a cargo manifest. Upon translating the manifest, Hoshi learns that the Osaarians recently attacked a Xindi ship.
Intrigued, Archer once again confronts Orgoth, demanding to know everything the Osaarians have learned about these mysterious aliens. Orgoth claims not to know anything, but Archer isn't ready to let him off the hook. The captain drags the Osaarian to an airlock hatch, locking him in and initiating the decompression cycle. Realizing that the captain is willing to kill for this information, Orgoth finally relents, revealing that the Osaarians took more than food and supplies from the Xindi — they downloaded the Xindi database. Orgoth also provides the access codes to the Osaarians' main computer.
With Enterprise's systems back online, Archer prepares to engage the Osaarian ship. As the two vessels battle it out in a fire fight, Mayweather maneuvers Enterprise close enough for Hoshi to access the Osaarians' computer. She manages to download the bulk of the Xindi database and Enterprise successfully defeats the Osaarian vessel. Since Orgoth assisted the crew, Archer sends him back to the Osaarians. Orgoth, however, cannot help but taunt Archer as he leaves, noting that mercy will not serve the captain well in the Expanse.
Having gained a wealth of new information on the Xindi, Archer settles in, preparing to study it all. The search for these mysterious aliens continues ...