Uncharted space, 2347. The USS Unity is conducting scans of a particularly empty area of space when things suddenly begin to go haywire. The ship is never heard from again. Presumed destroyed, it is not until the USS Resolution finds it in the middle of the Borderlands that the Klingons are finally absolved of its destruction. But what really happened to the now derelict ship, drifting alone in space?
En route to their first mission within the Borderlands, the USS Resolution discovers a derelict ship adrift not far from the Klingon neutral zone border. The ship is identified as the USS Unity, a Constitution-refit class (one of the last) which had gone missing and presumed destroyed over 50 years ago. Not able to get a reading on anything, an away team beams over to the ship to make an attempt to figure out what happened and to try to restore power so that she could be taken back to Starbase 118 to be decommissioned properly.
When the away team arrives, they discover not only the complete lack of power and life support, but the dead bodies of the entire crew all over the ship. Thanks to the relative lack of air for what seemed to be quite some time, and a lack of gravity, the bodies are mostly intact and have not degraded over the time they had been dead. The task of tagging them and cataloging who they are to bring closure to their families begins as the away team looks to restore power. Some of the bodies are transported over to the Resolution, where the CMO has set up a shuttle bay with similar characteristics to house the bodies and prepare them for proper burial.
A second team transports over to investigate another strange reading on the Unity, but stays only a short time when they are shown one word on a briefly powered console - 'exterminate'. No sooner had they beamed back to the Resolution with this new news, and the power was brought up on the Unity, than the once derelict ship raised its shields and began firing on the Resolution.
The out of date weapons proved to be no danger to the Resolution, which was much more maneuverable and easily got itself out of the way, moving just out of range while trying to figure out their next move. Meanwhile, on the Unity, the away team struggled with strange instances of telepathic connection with whatever the creature was by those members of the team with telepathy. From strong emotional feelings to visions, the team tries to figure out what it is that has locked them out of the computer and has started an attack on the Resolution. Unable to contact the other ship, they start planning a way to take down the shields or the weapons.
Back on the Resolution, some wounded are taken to sickbay following the first rumbles of the attack while the bridge crew does what they can to try to communicate with the entity. Simple hails do not work, but other ideas come up and are attempted. More and more creedence falls to the idea that they are dealing with a fearful animal versus a malignant being that wanted to hurt them. With life itself in the balance, the captain refuses to walk away having condemned anyone or anything to their end.
Splitting up and putting the team in danger from radiation, the entity, and other unknown potentials, the away team finds themselves able to bring down the shields and cut power to the phasers, enabling the Resolution to transport them back. Minor injuries are treated in sickbay, along with a case of radiation poisoning from the phaser cutoff on the Unity, as another team gets to work looking into the console that had originally spelled out 'exterminate' in the cargo bay of the Resolution. Together, the crew puts their collective specialties together to understand just what they are up against, and how to split it from the ship they had discovered.
Mass visions continue to take place, one taking out the acting CEO. Before he collapses, he claims the entity is trying to take over the Resolution, needing a certain form of radiation to continue to feed and grow. Aboard the Unity, the creature follows its instinct, converting food (energy) into waves that it doesn't realize are wrecking havoc on telepathic members of the crew. Stronger waves even start to impact those around telepathic members, allowing them to see events that the creature doesn't even understand. It is now up to the crew to figure out what it all means, and how to preserve the life of the being if possible, without allowing the Resolution to succomb to the same fate at the Unity.