Cassandra's been focused on her brain tumor after a medical check-up, and her time is running out. Coincidentally, the Librarians' latest target of investigation is a spa that completely rejuvenates its clients...until they walk into sunlight and turn to ashes. Vampirism is clearly the cause, but when your mortality is limited, can it really be called a problem?
Elsewhere, Flynn's set up some romantic time for Eve, knowing that he'll have to make a Heroic Sacrifice in the near future to stop Apep.
This episode makes use of the following Tropes:
- Antagonistic Offspring: The mother running the spa is slain by her son Tomas.
- Ambiguously Bi: Cassandra not only asks Jenkins on a date, but seems legitimately upset when he refuses. Then she and Estrella become very close and even share a kiss. Both possible relationships though go nowhere, as Jenkins is sworn to another and Cassandra decides to stay with the library.
- Arbitrary Skepticism: Both Jacob and Jenkins insist that there are no true causes of spontaneous human combustion. Vampires, however, are well-known to burst into flames in sunlight.
- Batman Gambit: While Estrella and Tomas are fighting, Cassandra grabs a stake and approaches Tomas. Tomas stops her, asking if she really thought she could stab him in the heart with the stake. She admits she didn't, and was planning on giving the stake to Estrella, who then uses it on Tomas while he's still facing Cassandra.
- Big Damn Heroes: Jenkins saves Jake and Ezekiel from a group of harmful vampires with a silver sword and dagger.
- Call-Back: To Carsen's adventure with Vampires.
- Even the Girls Want Her: Estrella and Cassandra bond over the course of the episode.
- Five Stages of Grief: Cassandra seems to be exhibiting them throughout the episode. At first, she's in denial, overdoing her cheerful happiness. While at the spa, she expresses unfounded anger that they give false hope to the terminally ill. Later on, Estrella points out that Cassandra has moved on to bargaining.
- Foreshadowing:
- Jenkins tells the LITs that there's no magical precedent for spontaneous human combustion. Note his emphasis on human.
- Upon first arriving at the spa, the LITs are told that mirrors aren't allowed there.
- Ezekiel notes the utter absence of garlic at the spa.
- Forgot About His Powers: When Tomas tells his Mooks to hold Jake and Ezekiel, they Flash Step and grab them from behind before the Librarians can so much as twitch. Later, Jake and Ezekiel are able to fight the vampires off without much difficulty, even though the vampires are supposed to be much more powerful and faster. The same applies when Jenkins shows up. There's no explanation for why the vampires don't Flash Step away from him, not giving him a chance to use his sword. It's possible they were panicked enough by Jenkins massacring the first few that they literally forgot about their powers, or else just that it's Rule of Cool.
- Friendly Neighborhood Vampires: Estrella and her mother didn't feed on humans and hosted the spa with the intent to heal people. However, some of their followers were not so friendly.
- I Just Want to Be Special: Cassandra declines treatment for her tumor, even knowing she'll die, because she believes the perception it granted was what qualified her as a Librarian.
- Lesbian Vampire: Estrella takes an instant liking to Cassandra and spends most of the episode trying to convince Cassie to stay at the spa with her.
- Living Forever Is Awesome: Estrella attempts to convince Cassandra of this, so that she doesn't have to choose between life and her hyper-intelligence.
- Magic Meteor: Moissanite is a rare mineral and the samples at the spa were carried there by a meteor centuries ago, enriching the landscape and opening up natural springs. Exposure coats the cells of vampires and shields them from UV radiation, allowing them to survive in the sun for up to a week.
- Mayfly–December Romance:
- Cassandra asks Jenkins out on a date soon after her check-up.
- There is also her blooming relationship with Estrella, who is at least more than 50 years old.
- Mook Chivalry: The vampires attack Jenkins one at a time, giving him a chance to use his silver sword to ash them. They also seemingly forget that they're vampires and have Super-Strength and Super-Speed (something they demonstrate a few minutes earlier).
- Our Vampires Are Different: Moissanite-rich water gives them immunity to the sun's rays. The lady running the spa and her daughter, Estrella, are content to stay within the moissanite-enriched grounds and refuse to victimize their clients. Her son and some of their employees, however, plan to isolate the antidote to thrive outside.
- Power Limiter: Cassandra's powers aren't caused by the tumor. They are (or were, anyway) supressed by it.
- Shout-Out: When they make the realization that they are dealing with vampires, Jacob looks at his hand and says he really hates vampires. Christian Kane played recurring villain Lindsey McDonald on Angel, where his character's hand was cut off by the titular hero, a vampire cursed with a soul. (This was confirmed to be a shout out on Kane's Twitter feed.)
- Stellar Name: Estrella.
- Suicide by Sunlight: Sofia tried this, which is how she discovered her sunlight immunity.
- Vegetarian Vampire: Estrella has, apparently, not fed on anyone for the past several decades. It's implied that her mother hasn't either. However, Tomas and others like him aren't satisfied with this life and want to go out into the world, ruling over humans as daywalking vampires.
- Villain Has a Point: When Estrella finds the ashes of her mother with Jake and Ezekiel standing over her (and Ezekiel has a veritable anti-vampire armory in his coat), she immediately assumes they killed her. They tell her about the secret lab in the spa and tell her that its presence will prove their innocence. Tomas then tells her that even if the lab exists, it doesn't prove that they're not murderers. Sure, he's just covering his ass, but the argument is valid.
- Wham Episode: Cassandra's tumor nearly kills her, and it's amputated out...but not only does she still have her gift after, she seems to gain the ability to influence the minds of others.
- Who Wants to Live Forever?: Estrella and Tomas's mother Sofia explains that when she came to this place decades ago, she was weary of her immortal life. After swimming in the beautiful pond, she said goodbye to her family and went out to meet the sun... and nothing happened. The water (well, the microscopic meteor fragments in it) protected her from the sunlight. After first being angry at being cheated, she changed her mind and embraced her new life.
