"Given enough time, evolution can do some pretty amazing things."
— Dr. Janet Fraiser
SG-1 and Dr. Fraiser are called out to the Antarctic site where the second stargate was found after a young woman is uncovered perfectly preserved in the ice.The research team discover that the woman — whom they dub "Ayiana" — is several million years old, causing Carter and Fraiser to speculate that she might have belonged to the race who originally built the gates, but the investigation is brought to a halt when team members begin to fall ill with a mysterious disease.
"Frozen" provides examples of the following tropes:
- Cliffhanger: The episode ends with O'Neill in a coma and being carried through the gate to receive a Tok'ra symbiote for implantation after succumbing to the virus.
- Contamination Situation: Once it becomes clear that Ayiana is carrying some kind of contagion, Fraiser declares the research base to be under quarantine.
- Continuity Nod
- O'Neill sarcastically states that it's "great to be back" in Antarctica.
- Carter mentions that Jonas is "a bit of a weather freak".
- Fraiser compares Ayiana's brainwave pattern to that of Cassie when she was suffering the effects of Nirrti's experiments and of O'Neill when he had the Ancient database downloaded into his brain. She also mentions that they have witnessed firsthand with Daniel's ascension how human beings can be transformed into something more powerful.
- Doctor, Doctor, Doctor: Goes on for an absurdly long time when Carter and Fraiser are introduced to the scientists at the research base, until O'Neill puts a stop to it.
- Doctor's Orders: Fraiser states "that's an order" after telling the others to get some sleep, despite the fact that O'Neill outranks her. However, it's been previously established that she has seniority when dealing with a medical crisis.
- Healing Factor: Ayiana is shown to be able to heal superficial injuries on her own.
- Healing Hands: Ayiana is able to cure most of those infected with the virus by laying hands on them, but unfortunately...
- Heroic Sacrifice: ...doing so weakens her to such an extent that she succumbs to the virus herself, and she ends up collapsing before she is able to save O'Neill.
- Human Aliens: Since Ayiana is likely millions of years old, the team realize that she must have originated on another planet, making her the first human alien they've encountered who wasn't transplanted from Earth by the Goa'uld. Carter even points out how astronomically unlikely it is that life on two entirely different planets could have evolved to end up more-or-less identical.
- Human Popsicle: Ayiana has been frozen in ice under the Antarctic for millions of years, and suffers few ill effects after being defrosted. Frasier specifically comments on how unusual it is that Ayiana's cells are even intact.
- Meaningful Background Event: While Carter and Fraiser are geeking out over the implications of Ayiana possibly being one of the Ancients, Dr. Michaels can be seen collapsing on the security footage that's playing on the monitor behind them.
- Meaningful Name: Dr Michaels gives Ayiana that name as it is from the Cherokee for "eternal bloom".
- Nice Job Breaking It, Hero: The scientists thaw out Ayiana without wearing any protective gear, and only after the fact do they consider the possibility that she could be carrying all kinds of pathogens.
- 90% of Your Brain: Fraiser mentions that Ayiana is using parts of her brain that would be dormant in most humans, much the same as O'Neill was able to do after using the Ancient repository.
- Precursors: Fraiser speculates that Ayiana could well be one of the Ancients, and if that's the case then it's possible that her kind could have deliberately engineered human evolution.
- Typhoid Mary: Ayiana initially acts only as a carrier of the disease while transmitting it to everyone else; however, this is eventually subverted, as healing the others weakens her to such a degree that she is no longer resistant to the disease.
- The Voiceless: Ayiana can speak, but she doesn't say very much and mostly communicates in gestures. Initially, considering that she speaks a language millions of years older than humanity itself, it isn't entirely surprising she decided not to bother. After, once she starts understanding Jonas, it's possible that she either understands the meaning of what he's saying rather than the words, or - as in Real Life - finds understanding easier than speaking.
- The Watson: Jonas acts as this, allowing Carter and Fraiser to explain the scientific/medical goings on.
