O'Neill accidentally interfaces with an alien device which downloads all the knowledge of the race who built the stargates into his brain, at the cost of his sanity and eventually his life, unless the team is able to find a cure in time.
First reference to The Ancients.
"The Fifth Race" provides examples of the following tropes:
- 90% of Your Brain: Played straight; Fraiser cites the (discredited) adage about humans only using 5-10% of their brain, and then goes on to say that O'Neill is up to 90% post Ancient upgrade.
- Although it was 90% at a single time compared with the normal 5-10%.
- Argument of Contradictions: Jack and Daniel descend into this at the briefing room table, when Jack randomly starts speaking Ancient. Made all the more amusing by the way Hammond looks back and forth between them like he's watching a tennis match.Daniel: You just said that there's nothing cruvus with you.O'Neill: I did not.Daniel: Yes, you did.O'Neill: No, I didn't.Daniel: Did.O'Neill: Didn't.Daniel: Did.
- Binary Suns: Carter and Teal'c get stranded on a planet with a second sun that didn't show up on the initial probe footage, which turns out to be a problem since it means that the atmosphere is liable to get significantly hotter than they anticipated.
- Boxing Lessons for Superman: O'Neill tries to teach Teal'c how to box at one point. He doesn't really get it.
- Continuity Nod:
- The "meaning of life stuff" from "The Torment of Tantalus" is mentioned several times.
- A subtle nod to "Solitudes": In both episodes, the stargate draws far more power than normalnote , and as a result travelers are hurled out of the wormhole.
- Deadly Upgrade: O'Neill gets all the knowledge of the Ancients downloaded into his brain; the only downside is that it completely overwrites his ability to speak or comprehend English - or any other language - and will eventually lead to his death if left unchecked.
- Death World: The planet that Carter and Teal'c get stranded on is definitely this as a result of its Binary Suns; Carter speculates that the daytime temperature could reach up to 200°F (or 93°C), very close to the boiling point of water.
- Deus ex Machina: O'Neill is able to gate to the homeworld of the Asgard, who extract the Ancient knowledge from his brain and send him back to earth.
- Either "World Domination", or Something About Bananas:Daniel: Uh, well, my translation's a little bit vague. Um, I think the circle means "the place of our legacy"... or it could be "a piece of our leg," but the first seems to make more sense.
- Foreshadowing: When the team first enters the Ancient facility, O'Neill calls the trip "an intergalactic waste of time." This episode featured the first time the Tau'ri travel outside of the galaxy.note
- On a series-wide level, the ancient device reacts to Jack's presence and no one else. While the team suspects its sensitive to the presence of a symbiote, its more likely it reacted to Jack's ancient gene, which wouldn't be revealed for years.
- Friendship Moment: Quite a bit between Jack and Daniel, due to the fact that Daniel is the only one who can make any attempt at communicating with O'Neill as he gradually loses the ability to speak English.Daniel: And bottom line, sir, what about Jack? [...] I can't leave him like this. And I won't.
- Indo-European Alien Language: The language of the Ancients is very closely related to Latin.
- Justified, given the Ancient Astronauts premise of the series and that it is later revealed that the Ancients built the stargate network, meaning they also visited Earth either before or during the beginning of human civilization.
- My Skull Runneth Over: O'Neill's mind steadily degrades over the course of the episode, to the point where he can no longer understand English and barely seems conscious of what he's doing at any given time.
- Neuro-Vault: The Ancient repository downloads all the knowledge of the Ancients into a person's mind.
- Never Give the Captain a Straight Answer: Teal'c tells Hammond that his presence is required in the control room. It's because Jack is messing with the computer under the influence of the alien device.
- Noodle Implements: O'Neill collects random Earth components and a staff weapon power cell, and with them builds a power supply capable of dialing an eight-chevron address.
- Nothing Is the Same Anymore: Thanks to Jack's actions and ingenuity this episode, the Asgard begin taking a much more active interest in the Tau'ri moving forward (which will lead to their eventual alliance with Earth). The concept of an 8 Symbol Address is also introduced, opening new storytelling avenues for the franchise (though this really won't come back into play again until Stargate Atlantis).
- Precursors: The first reference to the Ancients, long before they had firmly established themselves as neglectful.
- Right for the Wrong Reasons: Recalling how the device that downloaded the Ancient knowledge into O'Neill didn't respond to Teal'c, it's speculated that it was programmed to avoid giving such knowledge to a Goa'uld. It is eventually established that O'Neill has the Ancient gene allowing him to use their technology, confirming that the device recognised a difference between O'Neill and Teal'c but it was responding to something O'Neill had that Teal'c didn't, rather than the other way around.
- Screw You, Elves!: O'Neill gives an impassioned speech to the Asgard claiming that even if humans "aren't ready" for some things, they're already out there and doing the best they can. Notably, this seems to be in large part what helps him to gain the respect of the Asgard, and they at least acknowledge that humans have a great deal of potential.
- Stupid Scientist: Siler and the other scientist brought in to try and get Carter and Teal'c home, who seem to be there for no other reason than to look useless.
- Things Man Was Not Meant to Know: Apparently the human brain is not evolved enough to comprehend the knowledge of the Ancients without going mad and eventually dying.
- Translator Buddy: Daniel attempts to be this for O'Neill when he loses the ability to speak anything other than Ancient, with varying success.
- Wham Line: This exchange in the gate room.Gate Operator: Chevron seven... is encoded?Carter: And it's not the point of origin.Hammond: What?![...]Gate Operator: Chevron eight is locked.
- You Are Not Ready: This is the Asgard's view of humanity, although they can see our potential. This is gradually subverted in later episodes.
