Castle's gimmick for this film involved generating publicity with a worldwide talent search for the young actresses who would fill the title roles. Many are not actually from the countries they're supposed to be representing. Also, the overwhelming majority of the girls are Bit Characters at best, with Candy herself and the Chinese girl Mai-Ling being the only ones of any real prominence in the story.
This film contains examples of:
- 13 Is Unlucky: This trope is presumably the reason for the inaccurate title.
- Cultural Translation: The girl who gets to drive the bus in the opening is different depending on which country you're in, i.e. it's the British girl in the British release, the French girl in the French release, etc.
- Dirty Communists: The primary villains are agents of Red China. There is also one Soviet villain as well as a Western traitor working for the commies.
- Disney Villain Death: The Soviet agent dies this way. Unlike in Disney, we do see him hit the ground, but from a distance so there's still no visible gore.
- Femme Fatale Spy: Candy learns how to be one while researching espionage:Candy: [reading in voice-over] The female agent must use all the powers of her sex. This is her own special advantage in the art of espionage. There are times when she must be beautiful, seductive, alluring. With these powers at her disposal, princes will bow, generals will quiver, and empires will crash! [speaking aloud] I'll have to try that. [giggles]
- Forbidden Friendship: Candy and Mai-Ling. They tease themselves about how naughty they're being:Mai-Ling: You know, you're the nicest American I'm supposed not to like.
Candy: And you're the nicest girl from Red China I'm never supposed to recognize.
- Hammer and Sickle Removed for Your Protection: Averted. The bad guys are explicitly identified as the Soviets and the Chinese.
- Karma Houdini: While the Soviet agent and the Western traitor both die, the Chinese communists ultimately face no punishment for their actions, which include murder.
- Leitmotif: "Frère Jacques" apparently represents the school.
- Never Trust a Trailer: The movie's advertising tries very hard to sell it as a horror film rather than the spy film it actually is, apparently just because Castle was known for horror. Even the inaccurate title seems to be aimed at selling it as horror.
- No Name Given: Many of the girls are only ever identified by their country. In the opening credits, only Kathy Dunn and Lynne Sue Moon (Candy and Mai-Ling) are listed with their characters' names. The rest are listed by the countries they represent, even the ones whose names are actually mentioned in the movie.
- Nonindicative Name: You'd think a movie titled 13 Frightened Girls might actually contain thirteen girls rather than fifteen. The girls aren't especially frightened either.
- Precocious Crush: Candy has one on Wally.
- The Runt at the End: Mai-Ling is noticeably smaller than the other girls, and follows at the back of the line.
- Split-Screen Phone Call: Used for a series of telephone conversations in one scene.
- Was It All a Lie?: After finding out about Candy's spying activities, Mai-Ling immediately declares that Candy's friendship with her was all a lie even as Candy tries to explain that it wasn't.