Datalore
While this episode mines nearly every "evil twin" cliché that springs to mind (well, OK — Lore doesn't have a goatee), the introduction of Data's doppelganger brother makes way for the wonderful saga of Data's "family." And when Lore impersonates Data, we get a provocative look at what our favorite android might be like if he were to completely malfunction. Brent Spiner is excellent in the dual role, particularly during the androids' tense final face-off.

The Measure of a Man
This episode raises the tantalizing question of Data's rights as a being who is also a machine. When Commander Bruce Maddox wants to disassemble Data in order to create more androids for Starfleet's use, Data protests. What follows is top-notch courtroom drama, made all the more tense by the fact that Riker is assigned the role of prosecutor. The moment wherein Riker simply switches Data off is chilling, calling into question the android's right to self-determination. For Data, making his way in the universe as a decidedly unique being is an issue that will be raised time and time again.

The Offspring
In one of Trek's most touching hours to date, Data creates an android "daughter" named Lal. When Lal's programming begins to surpass her creator's and she develops emotions, her neural system fails. While Data's initial attempts at fatherhood are somewhat amusing, it is his poignant farewell to his offspring in the episode's final scene that gives the hour its punch. The moment is made all the more bittersweet by the fact that the android cannot feel the pain, grief and love expressed by Lal. Here, we see Data at an early stage in his slow understanding of humanity ... and are left to wonder at what is to come.

The Most Toys
The very nature of Data's being is called into question once again when wily Kivas Fajo adds the android to his collection of one-of-a-kind treasures. This episode offers us a hint that Data is not just a mere observer of humanity. At one point, Data has Fajo at gunpoint — he's beamed back to Enterprise before anything can happen, but we learn that the android was firing a weapon just as he was transported. Was Data really about to commit murder? Though he refuses to discuss the incident, we are left with an intriguing new shade of gray for this ever-evolving character.

Brothers
The saga of Data's most unusual "family" deepens here, as Data and Lore are summoned home by their creator, Dr. Noonien Soong. Soong is dying, but before he goes, he wants to give Data his final work — an emotion chip. Unfortunately, Lore attacks Soong and steals the chip before it can be implanted in Data. An outstanding triple role performance from Spiner distinguishes this one, as do the twisted — yet somehow strangely familiar — family dynamics. He may be the evil brother, but we even see a little twinge of sadness from Lore when he learns that Soong is dying. And of course, the promise of an emotion chip gives us a tantalizing glimpse of what's to come.

Data's Day
This fun, frothy episode gives us a taste of what it's like to be Data on a day-to-day basis. His general misunderstandings regarding humanity are funny and touching, and provide us with a fascinating look at how far our favorite android has come. Even though he now embodies various trappings of humanity — friends like Keiko and O'Brien, for example — Data still doesn't quite comprehend all of the complicated ins and outs of human interaction and relationships. The hour is also notable for a wonderful sequence that features Dr. Crusher giving Data dancing lessons.

In Theory
Finally, Data experiences what some might call the most complicated aspect of humanity: a romantic relationship. When fellow crewmember and musician Jenna D'Sora expresses an interest in the curious android, he reciprocates by setting up a program to guide him through the intricacies of romance. Unfortunately, Data's behavior is artificial and awkward — his incapacity for true emotion makes it difficult for him to replicate the experience of dating. Still, it's fun to watch him try, and we get the sense that he learns many new things about humanity from his relationship with Jenna.

Hero Worship
A young boy is saved from the wreckage of another Federation starship — and is immediately drawn to Data. What's so fascinating here is that we see Data's dilemma from the other side of the coin. The boy, Timothy, is traumatized by losing his parents, and longs for the emotionless state of an android. Rather than imitating humanity, Data finds himself in the awkward position of being imitated. Timothy even goes so far as to dress and style his hair like Data. In the end, Timothy deals with the loss of his loved ones. In a poignant moment, he acknowledges that even though he wants to be a human boy after all, he and Data will remain friends.

The Quality of Life
After fighting for his own rights as a sentient being, Data must fight for other lifeforms who also happen to be machines. The Enterprise crew is introduced to exocomps, complex machines that have advanced problem-solving capabilities. Later, when the exocomps begin to display signs of intelligence, Data determines that they are "alive." In the end, Data protects the exocomps when Riker wants to sacrifice them in order to save Picard and Geordi. It's fascinating to observe how far the android has come, as he takes what he's learned of humanity and applies it to these new beings.

Inheritance
The Soong saga gains yet another dimension when Data meets a woman who claims to be his "mother." Juliana Tainer is a scientist who was once married to Soong, and is happy to be reunited with her son. Tension arises between the two when Data learns the real reason as to why he was left behind at Omicron Theta. All of this is fascinating enough on its own, but the real wrinkle comes with the revelation that, unbeknownst to her, Juliana is actually a Soong-created android. The scene in which Data decides not to tell his mother of her true nature is wonderfully touching, and the episode is invigorated by a warm performance from the excellent Fionnula Flanagan (Enina Tandro on Star Trek: Deep Space Nine and Ambassador V'Lar on Enterprise).

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