"Trust no one."
—The Maze of Bones, the first book in the first series
Quiz time: What is The 39 Clues?
A. Childrens' book series.
B. Web site
C. Collectible card game
E. All of the above.
The answer is E.
The book series (and, by association, the website, cards, and sweepstakes) deals with the Cahill family, one of the most powerful families the world has ever known, as almost every historical figure from the last five hundred years is related to them. The family is divided into one of four branches - the Ekaterina, who are the geniuses and inventors of the world, the Tomas, who are explorers and athletes, the Lucians, who are the spies, generals, and leaders, and the Janus, the artists, musicians, and authors.
When Grace Cahill, arguably one of the last genuinely nice Cahills, dies, she chooses to unveil her alternate will and kickstart a globe-trotting quest to find the source of the family's power. Such power - a master serum that can give anyone who drinks it the inventiveness of an Ekat, the strength of a Tomas, the artistic genius of a Janus, and the strategic skills of a Lucian - can only be found by assembling all 39 Clues.
Our story begins when Amy and Dan Cahill, orphans who live with their disinterested great-aunt Beatrice, attend their grandmother Grace's funeral and the reading of her will. There, along with an assortment of...colorful...distant relatives, they make the choice: one million dollars or the chance to find the Clues alongside au pair Nellie Gomez. They choose to receive their first Clue, and are subsequently thrown into a five-hundred-year-old web of backstabbing, lies, and deceit. The first series follows them through the Clue hunt as they travel the globe, clash with their scheming relatives, and discover troubling truths about themselves and the Cahill family at large.
Flash forward two years to the beginning of the Sequel Series, Cahills vs. Vespers. The Clue hunt has ended with the victors, Amy and Dan, taking the recipe for the master serum but choosing not to recreate it, but a new threat has surfaced, and Grace revealed at the end of the first series that the Clue hunt was really only a practice run for this greater conflict between the Cahills and a rival group, the Vespers, who are allegedly so evil that they make Isabel Kabra look like Mother Teresa by comparison. Now the Vespers have begun making demands of the Cahill family, and the lives of seven hostages are at stake. Amy and Dan are once more sent on a trip around the world, frantically chasing down Vesper One's demands, while their teammates provide support from the Cahill Command Center, a computer lab that has been set up in Grace's mansion.
- Abusive Parents: This is most certaintly the case with Ian and Natalie since, Isabel Kabra is a Complete Monster who verbally degrades them on a regular basis. They both love her, and fear her simultaneously -- while also thinking that they lead the perfect lives because of all the wealth their family has They'd be Woobies if they weren't so nasty themselves!
- All Girls Want Bad Boys: Amy towards Ian.
- All There in the Manual: Inputting cards' codes on the website either unlocks a secret file or is part of a Clue Combo. Solving website missions' and inputting ultra-rare cards' codes unlocks one of the 39 Clues.
- Ambiguously Brown: The Kabras.
- London does have a large population of Indian-Brits. Isabel is described as lighter-skinned than her children, so it's probably Vikram who has some Indian ancestry.
- Ambition Is Evil: Everyone except Amy and Dan, the Lucians in particular.
- Ancient Conspiracy: The Cahill clan.
- Area 51: The Lucians are in charge of this location.
- Audio Adaptation: Read by David Pittu!
- Nellie is given a hint of accent, and the Kabras sound upper crust snooty (which is amazing)
- Badass Driver: While fleeing the Janus hideout, Dan becomes one of these.
- Nellie is one, too.
- Beethoven Was an Alien Spy: Beethoven certainly was, as well as Mozart, Neil Armstrong, Einstein, Churchill, Benjamin Franklin, Houdini, Bill Gates, and George Washington, among others.
- Big Bad: Isabel Kabra
- Big Screwed-Up Family: Where do we begin?
- Bluff the Eavesdropper
- Brother-Sister Team: Amy and Dan; Natalie and Ian.
- Changeling Fantasy
- Character Development: Amy overcomes a lot of her shyness.
- Everywhere in Book 10.
- All of the minor characters get this. If you look at reviews of the first book of the series, you'll see critiques of the "one-dimensional" relatives. Stick around until the middle of the series and interesting developments will begin taking place, especially - unusually for a childrens' book series - among adult supporting characters; the younger minor characters' development mostly happens in the last two books.
- Chekhov's Classroom: All the things Grace taught the Cahill siblings came in handy on the clue hunt.
- Chekhov's Skill: At first, Jonah's love of Shakespeare seems to have only been thrown in to show that Jonah has Hidden Depths, instead of just being a Jive Turkey and Teen Idol. It turns out that a knowledge of Shakespeare's lost plays is required to reach the end of the gauntlet and find the final clue.
- The Clan: Of the Cahills.
- Coincidental Broadcast:Used in Book #8.
- Death by Origin Story: Hope and Arthur.
- Did Not Do the Research: Averted. This IS a series intended to teach kids history, after all.
- Disability Superpower: Hinted with the Starling brothers.
- Everyone Is Related: Practically all the main characters are Cahills, with fans who make accounts on the web site also being "inducted" into the Cahill family.
- Evil Matriarch: Isabel
- The Family That Slays Together: All four branches, due to Feuding Families, though the Kabras are the best example.
- Feuding Families: The Lucian, Ekaterina, Tomas, and Janus branches are all feuding, especially the Ekaterina and Tomas.
- Foolish Sibling, Responsible Sibling: Dan and Amy, respectively. Dan gets somewhat better, though.
- Follow in My Footsteps: The reason most of the main clue hunters, including Amy and Dan, want to win the clue hunt, and are so ruthless in the way they go about it.
- Getting Crap Past the Radar: "Amy, what's a eunuch?" Forgive any misquotations, please.
- This gem from book 9, Storm Warning:
Amy: (reading) There's this witness testifying against Anne Bonny and Mary Read, who said that they wore 'Men's Jackets and long Trouzers, and Handkerchiefs tied about their heads.' And that 'the Reason of knowing and believing them to be Women then was, by the largeness of their Breasts.'
- Goofy Print Underwear: Dan has Pokemon on his, and Ian has pink dollar signs of all things on his, even though he's from Britian, where the dollar is not used.
- Green Eyed Red Head: Amy
- Sinead Starling.
- Grey and Gray Morality: Even Amy and Dan, who are by far the nicest and most principled clue hunters, will do morally questionable things from time to time.
- Handsome Devil: Ian Kabra seems to be molded perfectly for this. His sister Natalie is a gender flipped version of this.
- Heel Face Turn: Oh so many. It might even be a Heel Face Revolving Door for every Cahill. They all seem to have ulterior motives.
- By In Too Deep Irina has basically switched sides and wants to help Amy and Dan -- but of course they don't believe her until the very end...
- Island Base: The Ekaterina have one inside The Bermuda Triangle. Also, Madrigals have one on Easter Island.
- There's also the original island home of the Cahills where the Gauntlet is located.
- Kill'Em All: Isabel's plan on Easter Island - she's even willing to kill her own children.
- Kissing Cousins: Almost any pairing in the book can be considered this seeing as almost every character is a Cahill. This is usually dismissed though, seeing as apparently half of Earth's population is one.
- Le Parkour: Created by the Tomas.
- Loads and Loads of Characters: Almost every historical figure for 500 years is a part of the Cahill family. That's a lot of people.
- Also applicable on a smaller scale - there are seven "teams" in the Clue hunt. In these teams, there are, in total, seventeen people. Nearly every one of these seventeen people gets point-of-view chapters in multiple books, as well as a great deal of Character Development. Then there are the minor characters, some recurring and some not, and the villains who are not officially part of any team.
- Hufflepuff House: Arguably, every single branch. Although the Lucians managed to get their hands on a vial of something-or-other in Book 1 from Ben Franklin, which then turned out to be the Lucian serum, part of the master serum.
- Hypocritical Humor: At one point in the series, Dan complains "I can't believe she cheated me - right when I was in the middle of cheating her!"
- Machiavelli Was Wrong: Well, he was certainly right in regards to Ian and Natalie's relationship with their mother. Until the last book, when they realize that while they loved Isabel they were only following her (mostly) out of fear.
- Never Found the Body: What happened with Alistair Oh in Book 3. Dan and Amy were genuinely upset about his death until... they found his dirty glove and realized he must have survived then left without them
- Never Trust a Trope: "Never trust a Cahill."
- Opposites Attract: Amy Cahill and Ian Kabra; see Unrequited Love Switcheroo below.
- Only a Flesh Wound: Natalie is shot in the foot.
- Parental Abandonment: Amy and Dan's parents were killed in a house fire.
- Ian and Natalie apply also
- It's not so much Parental Abandonment as it is abandoning their parents.
- Ian and Natalie apply also
- Parental Issues: Most of the characters have them.
- Photographic Memory: Dan has one.
- Put on a Bus: The Starlings are caught in an explosion rigged by the Holts and end up in the hospital for the next nine books, but they return in book ten.
- Redheaded Heroine: Amy
- Rivals Team Up: The Cahills and the Kabras in The Sword Thief.
- Sacrificial Lion: Irina and Lester
- Screw the Rules, I Have Money: Basically every Cahill BUT Amy and Dan
- Screw the Money, I Have Rules: Actually a subversion. Amy and Dan aren't above stealing and lying if it means getting any information at all on their parents and the fire that killed them.
- Serious Business: The 39 Clues.
- Although seeing as the prize for finding all 39 is super strength, intelligence, creativity and strategy skills that could grant you world domination... well, the way all the characters take it seriously doesn't seem too farfetched.
- Shout-Out: A lot. To Star Wars, Star Trek, Indiana Jones, Monty Python...
- Shown Their Work: Justified. In order to find the clues, Amy and Dan need to research the people and places connected to the clue hunt. Also, it's part of Amy's characterization to spout historical facts with little prompting.
- Sibling Team: Amy and Dan, Ian and Natalie, the Starling triplets.
- Sixth Ranger: The Madrigals are a Cahill family branch
- Smart People Play Chess: In the second book, Ian is said to have a very high IQ. In the same exact scene, he plays chess against a supercomputer.
- Someday This Will Come in Handy: See Chekhov's Classroom.
- Tall, Dark and Handsome: Ian
- Team Pet: Saladin, Grace's cat, who accompanies Amy and Dan on their adventures.
- Teen Genius: The Starlings.
- Teeth-Clenched Teamwork: Occurs whenever alliances are formed between teams. Of special note are the Cahills and the Kabras in book 3, and the Kabras and Irina in books 5 and 6.
- There Are No Therapists: Whoo, boy...
- Tomato in the Mirror: This should be two living Tomatoes and three dead Tomatoes in the Mirror. Book #7 has Dan Cahill revealing Cahill's family's branch. It happens to be Madrigals, a branch known for its secretiveness. The reason is explained at the end of Book #9, the Madrigals' main goal is to unite the all five branches of the Cahill Family.
- Twin Telepathy: Amy and Dan aren't twins, but they are siblings who are pretty close and always know what the other is thinking by reading each other's facial expressions. Some fanfictions make it practically telepathy in any case.
- Unrequited Love Switcheroo: Amy's always had somewhat of a crush on the fabulous Ian Kabra. After he "fakes" love for her and leaves her for dead in a cave she eventually starts getting over him. Too bad he's starting to develop genuine feelings...
- Video Wills: How Grace starts the hunt for The 39 Clues.
- Was It All a Lie?: Type 2 occurs in the third book. Amy Cahill wonders this after she and her brother make an alliance with Ian and Natalie Kabra, during which Ian flirts with her. The alliance ends with the Kabras making off with what Dan led them to believe was the clue, and in the meantime trapping the Cahills in a cave.
- We All Live in America: See the Goofy Print Underwear entry above.
- "Well Done, Son" Guy: Isabel Kabra for her children and Bae Oh for Alistair, arguably.
- You Killed Our Parents: Amy and Dan, repeatedly, towards Isabel, Alistair, Cora Wizard, and the Holts.
- And, for that matter, Alistair towards Bae Oh.
- You Wouldn't Shoot Me: Ian tells Isabel that he doesn't believe that she would shoot her own daughter, Natalie.
Warning: By definition, it is impossible to discuss a Sequel Series without spoiling the first series, so expect a lot of spoilers.
The Sequel Series, Cahills vs. Vespers
- Adorkable: Amy's secret nickname for her boyfriend, Evan.
- Betty and Veronica: Male version with Evan as the Betty, Ian as the Veronica, and as of Dead of Night, Jake Rosenbloom as the Third Option Love Interest.
- Black and Gray Morality
- Darker and Edgier: Despite its slightly lower important-character body count, there's no doubt that Cahills vs. Vespers is darker than the original series...
- A huge amount of Mook deaths occur, many with a healthy dose of Nightmare Fuel.
- Besides death, there's an increase in violence, and the authors don't shy away from describing blood - see Only a Flesh Wound.
- Though the language remains kid-friendly, it's obvious that more liberties have been taken than in the original series.
- A Love Dodecahedron shows up in "Dead of Night".
- Girl Notices First: Amy has a crush on Evan months before they start going out.
- Hostage Situation: The premise of the series is that seven Cahills have been kidnapped, and Amy and Dan Cahill have to fulfill bizarre ransom requests to get them back.
- Hostage Video: How the Vespers prove that they have the hostages alive.
- Hypocritical Humor: At one point in The Medusa Plot, Hamilton Holt complains that "Those guys ripped off what we rightfully stole!"
- I Will Punish Your Friend for Your Failure: See Hostage Situation entry above and Revenge by Proxy entry below.
- Long-Distance Relationship: Amy and Evan start one of these (carried on mostly via phone) after Amy and Dan take off on their missions around the world.
- Not Quite Dead: Arthur Trent, fairly solidly confirmed in Dead of Night, although he hasn't made an actual appearance yet.
- Only a Flesh Wound: Nellie is shot in the shoulder and lives, although she needed to have the bullet removed to do so. The incisions were made by an eleven-year-old and the removal is done by a thirteen-year-old, both of whom are inexperienced, and the latter of whom is so squeamish about blood that she had her eyes closed while she removed the bullet.
- Parental Abandonment: As stated above, Ian and Natalie. Isabel disowned them. Also, Cora Wizard is no longer speaking to her son Jonah, and Amy and Dan's father is alive, meaning he left them to basically raise themselves for about nine years.
- Revenge by Proxy: When the Vespers think that Amy and Dan are trying to trick them, they shoot Nellie, but she survives.
- Sacrificial Lion: William Mcintyre
- Take Me Instead!: Amy tries to trade herself for the hostages.
- Teeth-Clenched Teamwork: Ian and Evan working together in the Cahill Command Center.
- We Have to Get the Bullet Out: See Only a Flesh Wound entry above.
Warning: The companion books may contain major spoilers for the first series, The 39 Clues, as well as minor spoilers for Cahills vs. Vespers.
Companion Books (Rapid Fire, The Cahill Files, and The Black Book of Buried Secrets)
- Stalking Is Love: It's revealed in Operation Trinity that Ian watches Amy before the clue hunt via a surveillance camera, and there isn't even a hint that the author thinks this is wrong. The entire scene even seems to have been thrown in solely to please the Amy/Ian shippers.