A Young Adult book series by Jennifer Lynn Barnes. The series focuses on the cheerleading squad of Bayport High, who, unknown to their fellow classmates, are actually a group of junior CIA agents. The story's protagonist is [[TheSnarkKnight Toby]] [[PlayfulHacker Klein]], a girl known for her skill at hacking computers and her distaste for the cheerleading squad. One day during school, she is invited to join the squad and, naturally, has no intention of actually taking part. However, when she discovers that her invitations have secret codes embedded in them, she becomes curious and attends a practice, at which point she learns the true nature of the squad and becomes their newest member.

There are currently two books in the series:

* ''Perfect Cover''
* ''Killer Spirit''

!!Tropes in the series include:
* {{Adorkable}}: Toby describes Noah as this. It's unclear whether she means it sarcastically or not.
* AllGuysWantCheerleaders: Toby's transformation into a cheerleader causes her to be adored by most of the male student population.
* AnnoyingYoungerSibling: Noah, but Toby loves him anyway and often protects him when he gets in over his head. (He has a bad habit of hitting on other people's girlfriends.)
* BecomingTheMask: Toby fears that this is happening to her in ''Killer Spirit.''
* TheCheerleader: Subverted. The members of the squad are indeed the most popular students in school, but their ditziness and/or bitchiness is simply an act to mask their true nature. (Chloe is ''genuinely'' bitchy to Toby, but it has less to do with her being a cheerleader and more with the fact that she feels threatened by Toby.)
* ChildProdigy: Zee graduated high school when she was eight or nine years old and had completed a Ph.D in Forensic Psychology by the time she was high school age.
* DistractedByTheSexy: Apparently, this is a common tactic for members of the squad.
* IdiosyncraticEpisodeNaming: Each chapter is named "Code Word: _______"
* OppositesAttract: Toby notices in ''Killer Spirit'' that Lucy - rather than teasing her about it, as the twins are - actually seems to have genuine feelings for [[AnnoyingYoungerSibling Noah]]. She's really not sure how to feel about it.
* PlayfulHacker: Toby. She once accidentally hacked the Pentagon because she thought that the website was a fake put up by another hacker.
* TheProfiler: Zee. She can psychologically dissect anyone, given enough time. She develops a thorough and accurate psychological profile of Toby within a few days of meeting her.
* {{Pyromaniac}}: Lucy. Her main criteria for judging the quality of alcohol is how flammable it is.
* SeriousBusiness: [[JustifiedTrope Justified]]. They do treat being a [[PomPomGirl cheer squad]] as SeriousBusiness, but only because they have to keep up the appearance of being ordinary cheerleaders so that no one will suspect that they work for the CIA.
* ShoutOut: When Toby first hears the anonymous voice of the person who gives the squad their orders, he says "Hello Girls." Toby has to resist her impulse to respond "Hello [[Series/CharliesAngels Charlie.]]"
* TheSnarkKnight: Toby is often sarcastic and flippant with, well, everyone, but she quickly develops a sense of loyalty to the members of the squad and, in particular, her partner Tara.
* TheSquad: Naturally.
* TheVoice: The person who gives the squad their orders. [[spoiler: Toby discovers that his true identity is Alan Peyton and that his brother is their enemy, but the squad leader is adamant that she forget this.]]