Cassandra Fraiser becomes dangerously ill on her sixteenth birthday, and begins to develop psychic abilities as her condition deteriorates. SG-1 returns to her home planet, and suspect that Nirrti is involved when they find an abandoned Goa'uld laboratory.
Last appearance of Cassandra, although she continues to be mentioned afterwards.
"Rite of Passage" provides examples of the following tropes:
- Bratty Teenage Daughter: Cassandra has fully evolved into this since her last youthful appearance.
- Continuity Nod:
- SG-1 returns to the planet where they first found Cassandra.
- Nirrti still has access to technology that can make her invisible, and the team use TERs to search for her on the base.
- The team realize that Nirti had been prisoner of Cronos since Fair Game but has apparently escaped after they Killed Cronos.
- A Day in the Limelight: One of the few episodes with a character focus on Fraiser during her tenure on the show.
- Evilutionary Biologist: It's revealed that Nirrti was conducting experiments on the children of Cassie's planet in the hopes that their evolution would eventually produce a human advanced enough to be the perfect Goa'uld host.
- Has Two Mommies: Really driven home during the opening sequence, with Carter and Fraiser trying to celebrate Cassandra's birthday with her while she's much more interested in going off with some boy.
- I Gave My Word: The heroes agree to let Nirrti go free in exchange for saving Cassandra's life, a bargain which they reluctantly honor at the end of the episode. Nirrti admits that if their positions had been reversed, she probably wouldn't have done the same.
- I Just Want to Be Special: Cassie seems to enjoy her new psychic powers a little too much and begs Fraiser to let the transformation run its course, despite knowing that it'll likely kill her.
- Madness Mantra: Cassandra repeatedly states that she "has to go into the forest".
- Mama Bear: Once she realizes that Cassandra can't be saved through ordinary medical means, Fraiser takes matters into her own hands by busting into Nirrti's cell and holding her at gunpoint, after knocking out the guard with a shot of morphine. To make this even clearer, Nirrti is only persuaded to help after Hammond informs her that the woman pointing the gun at her is Cassandra's mother.
- Not So Stoic: Fraiser's trademark unflappable professionalism cracks when the patient she's trying to save is her own adopted daughter.
- Obfuscating Stupidity: Cassandra lampshades O'Neill's habit of doing this when she mentions that he always calls the knights in chess "horses".Cassie: He always pretends he's not as smart as he really is.
- Put on a Bus: Cassandra never shows up again, although she does get a few brief mentions here and there in later seasons.
- Running Gag: O'Neill's explanation for how Cassie is able to move chess pieces with her mind is "magnets".
- Sensor Character: Cassie is able to sense Nirrti's presence while she's invisible, thanks to the naquadah in her blood.
- Sequel Episode: To both "Singularity" and "Fair Game".
- Ship Tease: Daniel and Fraiser have a brief moment when he offers to support her and they sort of hold hands and stare at each other for a while.
- Transhuman: Cassandra's gains an increased brain capacity and telekinetic powers, though she's returned to normal after Nirrti heals her.