The alien ship possessed a vast weapons array and a unique scanning device. The NX-01's encounter with this ship prompted Captain Archer to turn Enterprise around, on a course for Jupiter Station, in order for the ship to be outfitted with phase cannons. Meanwhile, Trip and Reed went to work on installing the prototype phase cannon.
Aliens from the ship used a shuttle to dock with Enterprise, boarding the ship to spy upon it. The aliens proved themselves to be seemingly impervious to phase-pistol fire, for they employed a sheild of sorts whenever fired upon.
Archer and crew managed to knock out the mystery ship's shields. Leaking drive plasma, the alien vessel fled. Never to be seen again...for now.