- "And though you are not sentient, Spot, and do not comprehend,
- I nonetheless consider you a true and valued friend."
Spot was a relatively fickle cat. She only took to Data and Reginald Barclay. In 2369, while taking care of Spot, Commander Riker was forced to go to sickbay when she scratched his face. The next year, Geordi La Forge borrowed Spot, since he wanted to see what having a pet cat was like. They did not get along well, either. A short time later, Data unsuccessfully tried to train Spot, which prompted La Forge to joke that it was actually Spot who was successfully "training" Data. On another occasion, Worf tried to give Spot commands, but Spot would not obey them. Data made 221 different formulas of food for Spot, many of which Spot did not care for. Later that year, Spot became pregnant by one of the twelve male cats aboard the Enterprise-D at that time. (TNG: "Timescape", "Force of Nature", "Genesis")
In 2370, Spot played an integral part in saving the crew of the Enterprise-D. A synthetic T-cell became airborne and infected the crew, causing inactive parts of their genetic code to activate and essentially "de-evolve" them. Data and Picard returned from an away mission to the chaotic situation. They made it to Data's quarters, where Spot transformed into an iguana. Her kittens, just recently born, were unaffected, due to the natural defense mechanisms in the placenta which protects infants from the mother's diseases while in the womb. This led Data to develop a cure using amniotic fluid from Nurse Ogawa, who was also pregnant. (TNG: "Genesis")
In 2371, Spot survived the destruction of the Enterprise-D. Data, via his newly-installed emotion chip, cried tears of joy over Spot's survival. In 2379, Spot was aboard the Enterprise-E with B-4. (Star Trek Generations; Star Trek Nemesis)
Spot first appeared in "Data's Day" as a male, long-haired Somali cat. In subsequent appearances, Spot was seen as a more common American short-hair orange tabby, but still as a male. It was only in the seventh season episode "Force of Nature" that Spot was first referred to as she. In "Genesis", she even gave birth. The Star Trek Encyclopedia jokingly suggests that Spot may be a shapeshifter or the victim of a transporter malfunction.
Spot was played by unknown long-haired Somali cats in his first two appearances and trained by Gary Gero and Scott Hart from Birds & Animals Unlimited. Spot's appearance was changed into an orange tabby cat beginning with the sixth season when Rob Bloch from Critters of the Cinema took over the animal casting and training. During his time on The Next Generation, Spot was then played by Monster, Brandy and Bud and later also by Tyler, trained by Rob Bloch and Karen Thomas-Kolakowski.
When it was decided that Spot would appear in the first TNG feature film, Star Trek Generations, Critters of the Cinema trainers Bloch, Thomas-Kolakowski and Kelli Cole trained the cats Monster and Brandy and their back-ups Spencer and Zoe. While Monster appeared in the scenes earlier in the film, when a more spunky Spot was required, Brandy was the cat seen at the end of the movie. Critters of the Cinema was not called back for the production of Star Trek Nemesis.
A scene that was cut from Star Trek Nemesis revealed that Worf was left to care for Spot. In the scene, Worf and La Forge were cleaning out Data's quarters. Worf heard a noise, and looked up. Immediately after, Spot jumped into his arms. Worf stated that he "was not a cat person." La Forge then said, "You are now." This scene, along with other deleted scenes, was added as an extra on the Special Edition DVD.
While the character of Data loved Spot, Brent Spiner is noted as possibly having an, albeit minor, dislike for the cat. In the commentary of Star Trek Generations, it was stated that he did not want to go back for Spot, and during an interview in the 2010 Wizard World in Philadelphia, he said, in a joking manner, that he thought the cat was "the stupidest actor I've ever worked with," saying that [s]he "never took a piece of direction, ever." Except for one time where "They" (presumably the writers) wrote in "Spot eats tuna out of a can. And he did it on the first take, otherwise we were there all day with that cat."
In the TNG relaunch novel Before Dishonor, Worf has assumed the role of caretaker for Spot after Data's death. Worf, after Spot assists with hunting down an alien infestation on the Enterprise, states that he finds her to be a warrior, who simply lulls people into a false confidence of a cat.