"If the effect of this spreads to the general public, we could have a massive disaster on our hands. People just aren't used to seeing unusual things the way we are."
— Maj. Samantha Carter
After returning from a mission, Jonas begins to see giant insect-like creatures on the base that nobody else seems aware of. The others suspect that he is hallucinating, but before long the effect spreads to other personnel and eventually the general public, threatening mass hysteria.
"Sight Unseen" provides examples of the following tropes:
- Arbitrary Skepticism: Everyone is pretty quick to initially dismiss Jonas' claim of giant bugs only he can see that can walk through walls, even though at this point they've already encountered multiple similar phenomena, including but not limited to the Ree'tou, the effects of the crystal skull, and the Tollans' ability to phase through solid matter. On the other hand, the biggest issue for them seems to be that he's the only one to see them. When he initially claims to have seen one, Hammond puts the base on lockdown and orders a full search, only lifting it once no evidence of it turns up.
- Another Dimension: Carter eventually figures out that the device brought back from the team's latest mission is allowing them — and anyone who comes into contact with them — to see into another dimension where the creatures exist.
- Big Creepy-Crawlies: The creatures appear as large, faintly transparent bug-like things, coming in various different types. Needless to say, this can be quite disconcerting for those who see them.
- Cannot Convey Sarcasm: As the team returns from a desert planet:O'Neill: Ah, General, you know how I love those sandy planets.Teal'c: The wind was most pleasant.(Beat)O'Neill: Jaffa sarcasm at its finest, General.
- Contamination Situation: Colorado Springs is placed under quarantine after it's discovered that the ability to see the creatures has been transmitted to the general population.
- Continuity Nod:
- When Jonas is the only one to see the creatures, he is concerned that the others might believe he is starting to suffer mental degradaton as a result of previous exposure to naquadria radition.
- Teal'c mentions that he does not enjoy fishing.
- Conspiracy Theorist: Vernon Sharpe and his grandmother, both of whom claim that he was experimented on during his time in the military. Jonas points out that in this instance they are right about there being a conspiracy.
- Distinction Without a Difference: It looks like O'Neill is going to use this trope, but then switches to By "No", I Mean "Yes":Carter: You only saw a flash of this creature. Are you sure it wasn't some kind of hallucination?Jonas: Are you suggesting I'm delusional?O'Neill: No, no, it's just... possible you were seeing something that wasn't entirely... Yes, that's what we're suggesting.
- Friendship Moment: Carter apologizes to Jonas for doubting his mental stability, assuring him that he is a valued member of the team and they need to start respecting him more.
- Hallucinations: The official cover story for the civilian population is that sightings of the creatures are merely hallucinations caused by a chemical spill.
- Mistaken for Romance: When Carter and Jonas go to interview Mrs. Sharpe, she comments that they "seem like a lovely couple". They go along with it.
- My Life Flashed Before My Eyes: Vernon says something to this effect when O'Neill starts shooting at one of the creatures, since he can't see them at this point.
- Properly Paranoid: Hammond has seen enough weird and dangerous stuff come through the Stargate that the first question he asks Carter is whether the device they brought back is dangerous, and he immediately orders a lockdown when Jonas claims to have seen something.
- Running Gag: Once again, O'Neill invites Carter to go fishing with him when the team is given some downtime, and once again, she declines in order to work on something in her lab.
- Shout-Out: To ALF when O'Neill tells Vernon the alien bugs are from Melmac. Vernon actually had seen the show and asks about the show.
- The World Is Not Ready: Said word-for-word by O'Neill to convince Vernon to keep quiet about the creatures.
- Wrong Genre Savvy: Vernon actually displays this twice in the episode:
- In a darkly humorous scene, O'Neill is getting gas at a station and chatting with Vernon the attendant when he sees one of the creatures for the first time. O'Neill pulls a gun and takes aim at the creature (which only he can see at this point). Not unreasonably, Vernon immediately assumes he's being robbed and puts his hand up before O'Neill corrects him.
- Vernon flees and tries to hide from O'Neill after he realizes that he's been seeing aliens and believes the government will kill him as part of a cover-up. Fortunately for him, O'Neill is part of a Benevolent Conspiracy. Now, if the rogue NID had been on his trail, that would have been a different story.
