Star Trek: The Next Generation’s beloved android Lieutenant Commander Data (Brent Spiner) features prominently in some of Star Trek’s most enduring episodes. Introduced in TNG's first episode "Encounter At Farpoint," Data was an advanced artificial intelligence who longed to become more human. Data was incredibly intelligent and physically powerful, but he struggled to comprehend human concepts like humor and was limited in his ability to process and express emotion. Spiner's understated performance could somehow evoke laughs and tears in equal measures, easily one of the most impressive acting jobs in Star Trek history.

By Star Trek: The Next Generation season 3, the show's successful format had been established, with each episode generally focusing on one member of the ensemble cast. With the exception of Captain Jean-Luc Picard (Patrick Stewart), Data tended to get the most spotlight episodes, as the show's writers and producers honed in on Spiner's magnetic performance early in the show's run. Data episodes ran the gamut, from two-part Borg epics to simpler stories where he tries to learn how to dance. Data is one of Star Trek's most enduring icons, with his empathy and drive to better himself evoking the best aspects of the science fiction institution.

10 Star Trek: TNG Season 7: "Phantasms"

After months of experimenting with a newly-discovered dream program, Data began experiencing bizarre nightmares. He experienced disturbing, strange visions of the USS Enterprise-D's crew, like Dr. Beverly Crusher (Gates McFadden) drinking from Commander William Riker's (Jonathan Frakes) head through a straw. When Data eventually began experiencing waking nightmares - one resulting in him inadvertently injuring Counselor Deanna Troi (Marina Sirtis) - Picard enters Data's mind through the holodeck, where he finds that Data's subconscious was trying to warn him about parasitic beings infesting the crew. It's a weird, claustrophobic episode that feels closer to a David Lynch movie than a typical TNG episode.

9 Star Trek: TNG Season 2: "Elementary, Dear Data"

"Elementary, Dear Data" sees Data and Lieutenant Geordi La Forge (LeVar Burton) attempting to enjoy a Sherlock Holmes program on the holodeck. The only problem is that Data knows the Sherlock Holmes stories in exact detail and keeps solving the mysteries too quickly. Geordi asks the holodeck to create an adversary able to challenge Data's intellect, which accidentally grants sentience to the program's version of Professor James Moriarty (Daniel Davis). What starts off as a lighthearted romp turns deadly serious when Moriarty takes Dr. Katherine Pulaski (Diana Muldaur) hostage, demanding to know more about his existence.

8 Star Trek: Picard Season 3: "Surrender"

After his death in Star Trek: Nemesis, Data's memory was restored via the information he ed into his brother, B-4 (Brent Spiner), and placed inside a new, advanced synthetic body, alongside the personality of his evil brother, Lore. The Star Trek: Picard season 3 episode "Surrender" sees Data and Lore battle for control of the new body, with Lore seemingly having the upper hand as he absorbs all of Data's memories. However, Data tricked Lore, as absorbing his memories essentially allowed Data to overwrite Lore and take control of his new body. After saving the USS Titan-A from Captain Vadic (Amanda Plummer), Data has a heartfelt reunion with his old crew many viewers had been waiting decades for.

7 Star Trek: TNG Season 6: "A Fistful Of Datas"

Lieutenant Worf (Michael Dorn) decides to take his son, Alexander (Brian Bonsall), for a holodeck adventure in the American Old West. ed in the festivities by Counselor Troi, the trio starts to notice something amiss with the program, as several of the characters begin transforming to look like Data. The glitch is caused by an experiment Data and Geordi La Forge are running on the ship's computer, and it very nearly has deadly consequences. It's a great showcase for Spiner to show a little range and way more emotion than normal, as he leans into seemingly every tried and true Western movie archetype.

6 Star Trek: TNG Seasons 6 & 7: "Descent"

The two-part "Descent" begins with Data and an away team engaging in an unexpected battle with a contingent of Borg drones. Data is forced to violently kill one of the drones, and to his horror, he feels emotional satisfaction when he does it. After struggling with the notion that he might only be able to experience negative emotions, it's revealed that the source of Data's emotions is Lore, who is manipulating his brother from afar as he builds an army of Borg drones extracted from the Collective. After being forced to torture Geordi, Data is eventually able to overcome Lore's influence and deactivate his evil brother before he can cause more damage.

5 Star Trek: TNG Season 2: "The Measure Of A Man"

Generally considered Star Trek: The Next Generation's first truly great episode, "The Measure Of A Man" sees Data's rights as a sentient being put on trial. The courtroom scenes are largely riveting, due in no small part to Patrick Stewart's absolutely powerhouse performance. "The Measure Of A Man" is not perfect - Picard's flirtation with the case's judge, Captain Phillipa Louvois (Amanda McBroom) is weird and out of place, feeling more like something that would involve Captain James T. Kirk (William Shatner). That said, the rest of the episode more than earns its reputation as a classic Star Trek story and the episode that put Data on the map.

4 Star Trek: TNG Season 6: "Birthright"

After being knocked offline in an Engineering accident, Data experiences a vision of his father, Dr. Noonian Soong (Brent Spiner), that he cannot explain. After consulting with Worf, Geordi, and Captain Picard, Data decides to recreate the accident to further investigate the vision. Data experiences another vision of Soong, who informs him that he's prematurely activated a dream program Soong designed to be turned on when Data reached a later stage of his evolution. Data decides to keep the program active and spend several hours a day "asleep" to more fully experience dreaming, bringing him ever closer to humanity.

3 Star Trek: TNG Season 4: "Data's Day"

"Data's Day" sees the titular android chronicling his day as he prepares for the wedding of Chief Miles O'Brien (Colm Meaney) and Keiko Ishikawa (Rosalind Chao), where Data is to serve as father of the bride. Data spends the day dealing with Keiko's cold feet, attempting select a gift for the wedding, and learning to dance from Dr. Beverly Crusher (Gates McFadden). There's a subplot about a Romulan spy, but the real joy of the episode comes in the seemingly mundane things Data does to better serve his friends on their wedding day. It's a relatively small scale, sweet episode that perfectly showcases why Data became such a beloved character.

2 Star Trek: TNG Season 4: "Brothers"

After inexplicably hijacking the USS Enterprise-D, Data travels to Terlina III where he encounters his creator Dr. Noonian Soong, who had been assumed dead for years. Soong had activated a homing device to lure Data to the planet, intending on gifting him a new emotion chip. Unfortunately, the homing device also brought Lore to Soong's doorstep. Lore managed to deactivate Data and impersonate him long enough for Soong to insert the new emotion chip in him before fatally injuring his creator. Data's final moments with his creator, who he finally acknowledges as his father, are deeply affecting, and all the more impressive considering Spiner was playing both roles.

1 Star Trek: TNG Season 3: "The Offspring"

To the surprise of everyone onboard, Data decides to become a parent, creating the cybernetic child known as Lal (Hallie Todd). With the help of Counselor Deanna Troi, Data actually takes to parenting rather quickly, guiding Lal through the early stages of her evolving sentience. Lal begins to showcase abilities even Data didn't have, like the ability to use contractions. Sadly, this was actually a side effect of a fatal flaw in Lal's positronic brain, and she would die in Data's arms. "The Offspring" is Star Trek: The Next Generation - and Data in particular - at its absolute best, asking intriguing questions about the nature of life while also being emotionally arresting.