SG-1 rescues the Tollans from the impending destruction of their homeworld. Back at base, said base is thrown into conflict when it turns out the Pentagon wants the Tollans' advanced technology. Kinda hard to keep hold of them when they can walk through walls, though. Things come to a head, Sam gives a Tollan named Narim a cat, and Daniel eventually dials the Nox so Lya can take the Tollans through the Stargate and help them find a new, Stargate-less world.
First appearance of Colonel Harry Maybourne and the NID.
"Enigma" provides examples of the following tropes:
- Apocalypse How: SG-1 come across the Tollan homeworld being destroyed by volcanic activity. Though this might have been something decades coming - Narim mentions never seeing an animal.
- Call-Back/Meaningful Echo: To The Nox, after Daniel disobeys Maybourne's orders (with the tacit approval of O'Neill and Hammond) and successfully helps the Tollan people to escape:Daniel: I'm just thinking about what that little guy with the funny hair once said.
O'Neill: "The very young often do not do as they are told"?
- Emotion Bomb: Narim is able to "record" his feelings for Carter and play them back to her.
- Emotions vs. Stoicism: The very stoic and reserved Omoc is contrasted with Narim who expresses open curiosity about Earth and develops romantic feelings for Carter.
- Fold the Page, Fold the Space: Omoc (Tobin Bell) explains their concept of interstellar travel to Daniel (Michael Shanks) with a stick, which he subsequently gets the wrong end of (apparently they don't fold space).
- Higher-Tech Species: The Tollan count as this, although they are technically human.
- In Your Nature to Destroy Yourselves: The reason why the Tollan refuse to share their technology; apparently they once did this with a neighbouring planet, which led to them destroying their entire world in the space of a day.
- Inhumanable Alien Rights: Maybourne shows up and announces that he has orders from the President to take the Tollan into custody and force them into sharing their technology, something that the main cast take issue with.O'Neill: These people do have rights, you know.
Maybourne: Do they? Under what nation's jurisdiction?
Daniel: How about basic human rights?
- Jerkass Has a Point: Considering the fact that the only reason Omoc doesn't want to stay on Earth is because he is worried that the Tollans' advanced technology will ultimately destroy us like it did to the other race in their home system, why anyone thought that he would be anything less than condescending towards the suggestion of moving to the vastly more primitive P 3X-797 (the Land of Light from the episode The Broca Divide) is anyone's guess.
- Jerk with a Heart of Gold: Omoc comes across like a dick, but he does have his reasons for being cautious and he does seem to warm up very slightly towards Daniel by the end.
- Loophole Abuse: Daniel is able to get away with going against orders to help the Tollans escape because he isn't in the military so he can't be court-martialed, and there's no way he could be tried in a civilian court without revealing the existence of the stargate program. Maybourne does threaten to have him fired, but it never amounts to anything.
- Moment Killer: Daniel inadvertently walks in on Carter and Narim kissing.
- Omnidisciplinary Scientist: Actually averted, for once; Carter explicitly states at the beginning of the episode that she isn't a vulcanologist and she has no idea how long they can survive on the planet.
- Outgrown Such Silly Superstitions: Daniel theorizes that this is the reason that the Tollan are a Higher-Tech Species.Daniel: Umm... we'd be colonising space right now if it hadn't been for the Dark Ages. There was a period of over eight hundred years where science was heresy and anathema. Maybe they didn't have that set-back.
- This also counts as Critical Research Failure, seeing as it was Christian Monasteries that, in Europe, preserved everything from Greece and Rome that they could, and science was sponsored by the Christian Church. And the Fall of the Western Roman Empire didn't mean the total fall of civilization, it meant a new ruling class took over. While certain technologies, such as concrete, were lost, for lack of materials (Roman concrete used a particular kind of volcanic ash in its construction, with a synthetic not being invented for over a thousand years). As for in the East, the Eastern Roman Empire (better known as the Byzantine Empire) continued just fine (and invented many wonderful things, such as Greek Fire a.k.a. Medieval Napalm), while the Islamic Empires eagerly absorbed as much Greco-Roman knowledge as possible and expanded upon it, particularly after contact with India, formulating a lot of the basics of modern mathematics, such as the Algorithm - which is part of why we use the Latin alphabet, but Arabic numerals.
- Narim later confirms this, mentioning the Tollan equivalent of angels as something that people believed in long ago, before the age of science.
- Secret Test of Character: Omoc claims that the Tollans' first escape from the base was one of these, to determine whether or not they were prisoners.
- Subspace Ansible: Omoc uses some kind of FTL communications device to send a message to the Nox homeworld.
- Temporary Love Interest: Narim is the first of many for Carter. He does reappear in a few later episodes, but their romance never really goes anywhere.
- Ungrateful Bastard: Omoc's reaction to SG-1 rescuing him and his people from death by volcanic eruption is mostly annoyance that they've been brought to such a "primitive" planet.
- We Have Those, Too: After Narim shares his feelings with Carter:Narim: We have a custom, that expresses more than words.
(he kisses her)
Carter: Yeah, we have that custom too.
- What We Now Know to Be True: Narim mentions that he's studied quantum physics, "among other misconceptions of elementary science."
- You Are a Credit to Your Race: The Nox says this about Daniel: "Your race has learned nothing... but you have."
- You Are Not Ready:
- Much like the Nox, this is why the Tollan refuse to share their technology with Earth.
- Lya says that humanity "has learned nothing".