Zobral's ship was a small, warp-capable starship owned by Zobral during the mid-22nd century. Sleek and wedge-shaped, it could penetrate narrow gaps in the planetary defense system on the Torothan homeworld without being detected.
In 2151, Enterprise received a distress call from Zobral's ship. The ship was taken aboard Enterprise, stored in one of the ship's launch bays, in order to receive necessary repairs. Two members of Enterprise's crew did some welding on the craft. It left shortly thereafter, heading to the Torothan homeworld. (ENT: "Desert Crossing")
Despite this vehicle clearly being referred to as a "ship" on screen and in the final draft script of "Desert Crossing", the scripted references to the vessel additionally twice called it "Zobral's shuttlecraft" and twice "Zobral's shuttle". The craft, in the same script, was described thus; "It's an exotic-looking vessel that shows signs of heavy wear and tear – scrapes, scorch marks, dents, etc."
In the final version of "Desert Crossing", Zobral's ship appears in three scenes, the first of which shows it in one of Enterprise's launch bays, the second demonstrates it making a departure from the starship, and the third features it behind Zobral as he starts to make his way off Enterprise for the final time. Though the first and third scenes suggested a full scale mock-up of Zobral's craft had been constructed, the ship was actually depicted as a CGI effect (as was scripted). Visual Effects Supervisor Ronald B. Moore elaborated, "There was some stuff that we had to cover up. For example, where the shuttle is there was a big welder and all of the cables and stuff. The only shot we did greenscreen was when Zobral turned and walked toward the shuttle. I was a little concerned about that because the director had him step up like he was going to go up into it. I was like, 'You know, I don't even know what this looks like.' The actor got up there, stepped inside and drove it away!" The effect was composited by Fred Pienkos at Eden FX. (Star Trek: The Magazine Volume 3, Issue 7, p. 57)
As evidenced by the final draft script of "Desert Crossing", Zobral's ship was intended to appear in a different scene after it was shown making its initial departure from Enterprise. A reuse of footage was scripted to depict it in a launch bay aboard the starship. However, Zobral's craft is clearly off-camera in the final version of this scene. The same script also didn't include the scene in which the ship actually makes its last appearance in the episode.
This vessel and its distress call which Enterprise detected were briefly referenced in the final draft script of "The Catwalk", in one of Captain Archer's starlog entries. In the final edit of that episode, though, there is a scene change that prevents the reference being more specific than to a generic vessel which sent a distress call Enterprise responded to.