"I have been around the galaxy long enough to know that knowledge is power, and understanding the technology that was left behind by the Ancients is the most powerful knowledge around."
— Vala Mal Doran
After completing Merlin's tests at Glastonbury and gaining access to his treasure, Daniel and Vala decide to test an Ancient communication device and find themselves in another galaxy, their consciousnesses inhabiting the bodies of a couple named Harrid and Sallis.
First appearance of Dr. Carolyn Lam and first mention of the Ori.
"Avalon, Part 2" provides examples of the following tropes:
- Aw, Look! They Really Do Love Each Other: Daniel cradling Vala's charred body after she's burned alive, and the uncharacteristic tenderness between the two of them after she's resurrected, are the first indications that they're actually starting to care about each other beneath all the sniping.
- Boldly Coming: Vala suggests that the real reason for the SGC is to meet women.Mitchell: She has a point, sir.Landry: I've been thinking I need to get out on an offworld mission or two.
- Book Safe: Daniel and Vala find Harrid and Sallis' copy of the Book of Origin (the Ori's holy book) with a hole cut out of the middle to hide the communication stones in the house they end up in.
- Burn the Witch!: Vala is chained to an altar and burned alive when the administrator decides that she's possessed after she neglects to recite a prayer over her tea.
- Chekhov's Skill: After Mitchell pulls the sword from the stone, he ends up having to fight a holographic knight, and states that he took fencing lessons in college. He then proceeds to get his ass kicked, and admits that he failed fencing.
- Continuity Nod:
- Daniel and Vala use the communication stones that previously connected O'Neill and Joe Spencer to travel to the Ori galaxy after retrieving the terminal from Merlin's treasure stash at Glastonbury.
- Daniel states that the ascended beings in his galaxy believe so strongly in free will that they won't even intervene to prevent that galaxy from being destroyed.
- Curse Cut Short: Daniel is midway through saying "And if you think I'm going to stay linked with you for the rest of my natural fucking life" when Mitchell cuts him off.
- Deadpan Snarker: Dr. Lam establishes herself as such in her debut episode.
- Death Is Cheap: Vala is resurrected by the Prior not five minutes after being killed.
- Descending Ceiling: The episode picks up right where the previous one left off, with Daniel, Vala, Mitchell and Teal'c trying to complete Ancient puzzles before they're crushed to death by the ceiling.
- Disproportionate Retribution: Vala is burned to death for forgetting to say a prayer, though by her own admission swearing at the administrator's wife after the fact probably didn't help.
- "Eureka!" Moment: Mitchell has one when he covers over half of one of the tiles from the Ancient puzzle he's supposed to be completing and realizes that the symbols are actually the numbers one to nine and their mirror images.
- Evil Learns of Outside Context: Daniel and Vala get their minds transported into the bodies of two people in a faraway galaxy, and inadvertently alert the Ancients' old rivals the Ori to the existence of human life in the Milky Way galaxy, which they wish to rule.
- Forced to Watch: Daniel is held back by the crowd and made to watch Vala's execution.
- Gender-Blender Name: Before finding out by talking with Fannis, neither Daniel nor Vala knew which of them was in the body of Sallis or Harrid as they had no idea which was the male or female name.
- Grand Theft Me: Daniel and Vala take over the bodies of two villagers from the Ori galaxy named Harrid and Sallis while their own physical bodies remain comatose at the SGC, though this is an unintentional example since they didn't realize what would happen before using the stones.
- Heroic Second Wind: Mitchell gets one when he's nearly defeated by the holographic knight, flashing back to his post-crash recovery before shoving Teal'c away and finishing the job himself.
- Hologram: The knight that Mitchell fights is one, though it's still capable of inflicting pain on him.
- La Résistance: Daniel and Vala meet a man called Fannis who tells them that he, along with Harrid and Sallis, is part of an underground group of heretics who oppose the teachings of the Ori.
- Magic Staff: The Prior carries one that he uses to bring Vala back from the dead.
- Mundane Solution: Subverted; Dr. Lee can't disconnect Daniel and Vala from the communication stones when their physical bodies start to crash and Mitchell makes as though to shoot the terminal, but Lee prevents him from doing so, pointing out that they have no idea what effect that might have and that it could very well make the situation worse.
- Nay-Theist: Fannis states that given the power of the Ori he doesn't doubt that they are gods, he just thinks they have some seriously questionable ethics.
- Oh, Crap!: Vala gets one after realizing exactly what her punishment is going to be.Administrator: May the fire burn you down to the ground and lay you in the dust.Vala: ...Fire?
- Only the Chosen May Wield: After Mitchell pulls the sword from the stone, only he can interact with it as a physical object; at one point he tries to pass it to Teal'c, and it just passes right through him.
- Only the Pure of Heart: After the team first complete the trials, the treasure fails to appear and the chamber starts to collapse, causing them to realize they must have done something wrong. Daniel points out that one of the conditions for passing the test was "truth of spirit" and demands to know what Vala took; she reluctantly turns over a silver coin, and once it's returned and Mitchell puts the sword back in the stone it came from, the treasure appears.
- Religion of Evil: There are more than a few hints about the nature of the Ori throughout the episode, most notably their extremely harsh punishments for breaking any rule and the fact that the people are prohibited from trying to learn about their own history.
- The Reveal: The Ancients are revealed to not have been the first evolution of Humanity as SG-1 (and the Atlantis Expedition) have long believed. They were originally interstellar refugees from a distant galaxy — and they had a very good reason for concealing the truth about their intergalactic origins.
- Shout-Out: The names "Harrid" and "Sallis" are a pretty obvious reference to When Harry Met Sally....
- Showing Off the New Body: Vala spends some time admiring her new cleavage after finding herself in Sallis's body.
- Suspiciously Similar Substitute: Dr. Lam is this for Dr. Fraiser, despite the fact that more than a year has passed in-universe since Fraiser's death.
- Translator Microbes: Daniel speculates that the people they encounter in the Ori galaxy are actually speaking a variant of Ancient and the communication stones are translating it into English for him and Vala.
- Treasure Room: Merlin's treasure is revealed this way after the team manage to pass all the tests.
- Tyrant Takes the Helm: Implied to be the case when Teal'c and Rak'nor complain about the "power-hungry" Gerak being voted in as the new leader of the Free Jaffa Nation, though Gerak himself doesn't make an appearance.
- Undercover as Lovers: Daniel and Vala pretend to be married to avoid drawing unnecessary attention to themselves in the Ori galaxy, since the people whose bodies they're inhabiting are a married couple.
- Unusual Euphemism: When Vala tries to explain what she said to offend the administrator's wife so much:Vala: I was trying to politely explain what was going on and then his wife started screaming and accusing me of being overcome, at which point I believe I suggested she might want to think about procreation... with herself.
- Worth It: Mitchell's reaction when the treasure appears, after he's narrowly avoided death by descending ceiling and holographic knight.
- Your Mind Makes It Real: Vala dies in the infirmary when her consciousness-in-Sallis is burned, establishing that even though their physical bodies aren't actually in the Ori galaxy, she and Daniel can still die there.
