Sheppard and McKay meet with Flora and Mardola, the royalty on a planet they've assisted and they offer to help the women's sister… Harmony, a pre-adolescent. They explain Harmony has been chosen as queen and thee is a rite of passage she must go on at the ruins within a forest. They appeal to Sheppard based on maintaining their alliance and he reluctantly agrees.
McKay and Sheppard take Harmony into the woods, while she wonders why Sheppard's put up with Rodney's impertinence. She also takes Sheppard's food from his pack as he goes to scout out a path, and it's clear Harmony is on the spoiled side. When Sheppard returns, he thinks McKay took his food and Harmony bursts into fake tears. Sheppard lets her navigate through the wood but they hear a strange noise that she identifies as a beast. Harmony says the beast won't harm her and insists on going on. While she argues with Rodney, Sheppard disappears… and men surround and capture them.
The men are Genii and insist that McKay turn Harmony over to them and say he's free to go. McKay considers it but Sheppard takes them down, having spotted them and slipped away to ambush them. Harmony says they used to trade with the Genii but her mother the queen banished them. They figure someone in the royal court is working with the Genii, and Sheppard goes ahead while Harmony and McKay argue. Sheppard returns to inform them there's more Genii looking for Harmony. Sheppard insists on turning back but Harmony wants to go on, and Sheppard overrides her.
At the palace, Mardola secretly meets with the Genii, who provide her with a communicator.
McKay suggests that they stun Harmony and carry her, only to find that she's slipped off. They search through the woods and find a cave and Harmony, who has started a fire and cooking food. They decide to wait, after hearing the beast again. Later they chat and Harmony suggests Sheppard become her queen: he defers. They then hearing the beast again and screams from the Genii. Sheppard goes to investigate, while Mardola calls to get an update from the Genii. Meanwhile, McKay advises her that Sheppard won't be interested and they manage to at least speak civilly to each other.
In the woods, Sheppard finds two dead Genii, savaged by the beast. He hides as the Genii finds the bodies but insist on hunting the trio down and killing them. Sheppard overhears them and returns to the cave and insists they go back. Harmony disagrees since they're close to the ruins, and insists the beast will avoid the ruins. Sheppard finally agrees and stuns the two Genii guarding the place. Harmony's pendant is supposed to glow but nothing happens, and McKay determines the ruins were constructed by the Ancients. McKay explains the ruins are a testing place and the "beast" is mini-drones. The pendant is a passkey and the Genii rearranged the control crystals.
McKay says he can repair the crystals given time while Harmony insists she can do it if she focuses. The Genii Field Captain calls the Genii and Sheppard tries to bluff through a conversation but it doesn't go well. McKay tries to make repairs while Shepard prepares for the Genii attack. They open fire and then ask for the girl, saying one of her sisters told them of her location. McKay isn't sure if it's working so Sheppard takes the pendant since anyone with the Ancient gene can activate the drone system. He makes a run for it and activates the system, and the drones mobilize and kill the Genii leader as the others run away. Harmony is duly impressed and declares McKay a hero. They return to the palace and search Mardola's quarters, finding the communicator and arresting her. McKay and Sheppard attend the coronation and Harmony unveils a painting of the epic adventure: with a brave Rodney and a cowering Sheppard.