For once, Stargate Command is being contacted by the people from another world rather than the other way around. However, these people, the Eurondans, sent three volunteers through their gate, who, of course, met Portal Slam deaths when they hit the iris. Their leader, Alar, contacts the SGC by video and begs for their help against an enemy which controls most of their world. In fact, the Eurondans are confined to an underground bunker.
Daniel, of course, wants to offer humanitarian help. Hammond agrees, saying they could not commit resources which would turn the the tide of an alien world war, and O'Neill is authorized to negotiate with the Eurondans, in the hopes that the SGC might be able to get some Imported Alien Phlebotinum. It turns out the Eurondans are indeed very advanced and that they're willing to offer all their technology in exchange for heavy water, which powers their defenses (notably, an energy shield protecting their bunker). O'Neill agrees, to the moral outrage of Daniel:
Teal'c: We are in fact offering them water.
Daniel: I was speaking metaphorically.
Back at the base, Daniel points out they don't even know how the war started and that Hammond did say they couldn't offer resources which would turn the war. Hammond admits he meant military assets, American lives, but Eurondans only need water. Daniel points out that there were two reasons not commit unconditional support: logistical and moral, and the moral question doesn't just "evaporate" once the logistical one becomes not a concern. Hammond agrees they should find out more about the war. At the negotiation, Daniel asks how the war started and Alar recounts how the enemy attacked them one day. Jack considers this sufficient and closes the deal.
But on the way back to the gate, Alar says Teal'c should not return since he is "not like us", apparently meaning dark-skinned. At this point, Jack finally recognizes that he may have just made a Deal with the Devil. After some digging, the team finds out the Eurondans' enemy are the "Breeders", so named because they reproduce with no set guidelines or strictures, and so come in all different shapes and sizes and colors... rather like the people of Earth. It turns out that while the Breeders did start the war, it was a preemptive strike and the Eurondans had been preparing to exterminate them for years before. Needless to say, the crew doesn't take too well to their new allies being Space Nazis and sabotages their defenses.
As Alar's bunker starts to collapse, the team returns to Earth. Just before O'Neill and Carter leave, Alar runs up to them, begging to go to Earth with them and offering all his knowledge of Eurondan technology. O'Neill warns Alar not to try following them (the team had explained the iris, at least in broad strokes, previously). After exiting the gate in the SGC, O'Neill orders the iris closed.
The gate deactivates with Alar presumably dead and Carter staring at O'Neill with a What the Hell, Hero? expression. The End.
"The Other Side" provides examples of the following tropes:
- A Nazi by Any Other Name: The Eurondans are revealed to be unapologetic racists who decided to commit genocide against those who don't practice eugenics. The premise of the whole episode is basically what would happen if SG-1 unknowingly travelled to Hitler's bunker at the end of World War 2.
- Always on Duty: O'Neill arrives at work several hours early to find Carter already in the control room, with Daniel joining them soon after the Offworld Activation alarms start going off. When he asks them what the hell they're doing there, Daniel claims he's hanging around due to the novelty of someone contacting them for a change, while Carter flat-out states that she never left base the night before.O'Neill: Didn't I order you to get a life?
- Atmosphere Abuse: Alar claims that the Eurondans live underground because the atmosphere is poisonous; while this is technically true, it's revealed that they were the ones who poisoned the atmosphere in the first place in an attempt to wipe out the "breeders".
- Attack Drone: The Eurondans use remotely-controlled drones to attack their enemy, which both O'Neill and Teal'c get to try firsthand.
- Bombers on the Screen: Through most of the episode we see the air war being fought on a fancy LCD table that also for some insane reason has physical models placed on top of it.
- The Conscience: Daniel is the first to insist that they provide humanitarian aid for the Eurondans after receiving their distress call, and when O'Neill and Hammond want to trade heavy water he urges them to consider the other side of the conflict. O'Neill is extremely irritated by this to begin with, but when he grows suspicious of Alar he changes his mind and encourages Daniel to keep asking questions.
- Discriminate and Switch: The team initially assume that the Eurondans are uneasy around Teal'c because he's Jaffa, which isn't exactly uncommon among the planets they visit, since the Jaffa are the foot soldiers of the tyrannical Goa'uld — but then it turns out that it's actually because he's black, and the Eurondans are Space Nazis.
- Distress Call: The episode opens with the Eurondans contacting Earth to request aid.
- Elaborate Underground Base: The Eurondans live in one to avoid the toxic atmosphere, though it's later revealed that they spent years planning it in advance and this was their plan all along.
- Fantastic Slurs: The Eurondans call the other people on their planet "breeders".
- Fighting the Lancer: O'Neill and Daniel spend the first half of the episode clashing over how to deal with the situation; O'Neill wants to provide heavy water to the Eurondans in exchange for some of their advanced technology and has Hammond's backing to do so, but Daniel thinks this is going too far as they can use the heavy water to power their weapons. The fight gets pretty ugly and personal by their usual standards, and there are times where Carter and Teal'c seem quite taken aback.
- First-Name Ultimatum: O'Neill and Daniel get into a round of this combined with Passive-Aggressive Kombat while they're attempting to negotiate over dinner with the Eurondans:Daniel: Jack...?O'Neill: Daniel...?Daniel: Shouldn't we ask them what they want the heavy water for?O'Neill: Oh, I don't think so.Alar: The power generated by your heavy water would be used to reinforce our defenses, Doctor Jackson.O'Neill: Daniel?Alar: ...And in due course, to strike back at the enemy.Daniel: Jack?O'Neill: Daniel. Shouldn't we have this discussion some other time?
- Freeze-Frame Bonus: When O'Neill shoots down the manned bomber as his unmanned drone collides with it, there is a split second before impact that you can see the crew in the cockpit. While this is obviously to show that the bomber had men in it to provide a development of O'Neill getting personally involved in the war like Earth is doing in a wider sense, one of the pilots has black skin. When no-one else shown so far has anything but white skin, which could give a sharp minded viewer a early revelation as to why the war is being fought.
- Heel Realization: O'Neill realizes that he's been unintentionally aiding fascists when Alar makes a comment about Teal'c being "not like us."
- Honor Before Reason: At the end of the episode O'Neill causes Alar's death rather than let him be taken prisoner by SGC, even though Alar had already expressed a willingness to exchange all his advanced technology just to save his own life. Given that Alar was basically Space Hitler (and would probably said anything to save his own ass), it seems O'Neill decided that letting him live was too high a price for said technology.
- Human Popsicle: The Eurondans are keeping thousands of their people in stasis pods until the day that they can reclaim the surface.
- Ironic Echo:O'Neill: Next time I tell you to shut up...Daniel: I didn't hear you tell me to shut up.O'Neill: What, too subtle for you?
- Later:
O'Neill: Daniel, shut up. That clear enough for you? - Karmic Death: O'Neill orders the iris closed after Alar follows them through the stargate, giving him the "bugs against a windshield" treatment.
- Literal-Minded:Daniel: Their whole world is in flames, and we're offering gasoline, how is that help?Teal'c: We are in fact offering water.O'Neill: Thank you!Daniel: I was speaking metaphorically.O'Neill: Well, stop it! It's not fair to Teal'c.
- My God, What Have I Done?: Downplayed, but O'Neill gets a moment when he realizes that he and Teal'c killed several people after shooting down what he assumed to be unmanned drones.
- Non-Answer: Teal'c again:O'Neill: So what's your impression of Alar?Teal'c: That he is concealing something.O'Neill: Like what?Teal'c: I am unsure. He is concealing it.
- Portal Slam: At the beginning of the episode, three Eurondans die this way when they attempt to reach Earth through the stargate and end up splattering against the iris. Comes back at the end of the episode in even darker fashion when O'Neill deliberately closes the iris on Alar.
- Power at a Price: The SGC has been hunting for advanced technology for three seasons, and now the Eurondans practically hand it over to them on a platter. All it would cost is abetting a group of Space Nazis in a genocidal war. Unsurprisingly, they don't take the deal.
- Spotting the Thread: The Eurondans being mono-racial isn't in itself unusual, as many gate worlds were established as colonies using populations taken from a single geographical location on ancient Earth. It's only after O'Neill sees that the Eurondans' enemies are multi-racial, and that their discomfort around Teal'c seems to be based on race and not him being a Jaffa, that he realizes he's been taking the side of Space Nazis.
- Stock Footage: As revealed on the DVD Commentary, the background cloud footage in the cockpit POVs was recycled from Firefox.
- The Teetotaler: While the others all have a glass of something with their meal, Teal'c claims that he "does not consume alcohol". It isn't clear if this is a Jaffa thing or a personal choice. It's also entirely possible that Teal'c's symbiote filters out alcohol like other poisons, making his consumption of alcohol wasteful and pointless.
- What the Hell, Hero?: The look that Carter gives O'Neill when he orders the iris closed on Alar.
