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->''From the sting of my curse she can never be free\\
Parsley, sage, rosemary and thyme\\
Unless she unravels my riddlings three\\
She will be a true love of mine''

''Impossible'' is a 2008 novel by Nancy Werlin, the first book of her Scarborough Fair Trilogy.

Lucy Scarborough is seventeen years old when she learns that the women in her family have been under a curse for hundreds of years - by their eighteenth birthday, they will have a baby, and then promptly go mad. Unless, that is, they can solve three tasks described in the ballad ''Scarborough Fair''. Lucy's ancestors have all failed at this task, but she is the first who isn't alone as she tries it. With her loving foster parents and childhood friend Zach, Lucy is in a race against time as she struggles to complete the seemingly [[ImpossibleTask impossible]] tasks.

A second book, ''Extraordinary'', which was released in 2011, takes place in the same world, but features different characters. It focuses on a girl named Phoebe, who learns that her friend Mallory, and Mallory's brother Ryland, are actually from the faerie realm, and that they are here to collect on an age-old debt.

The third book, ''Unthinkable'', was released in 2013. Fenella was the first Scarborough girl to fall under the curse. She rejoiced when it was broken - only to find that she was still trapped and very much alive in the faerie realm. After hundreds of years in captivity, she wants nothing more than the release of death, but she finds that she is unable to die. She makes a deal with the faerie queen to have a chance to break her life curse: she must perform three acts of destruction. What she doesn't expect, however, is that the three acts must be against her own family. There will be dire consequences for all of the Scarborough girls if she fails - but how can she choose to hurt them?

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!!These novels provide examples of:

* AllThereInTheManual: The official site [[http://web.archive.org/web/20170502090942/http://www.penguin.com/static/packages/us/yreaders/impossible/impossible/geneology.php had a list]] of all of Lucy's ancestors and their history, all the way from Fenella.
* BabiesMakeEverythingBetter: In the end of ''Impossible'', [[spoiler:Lucy breaks the curse and is free to live her life with her new child, who she names Dawn to represent the new beginning.]]
* ChekhovsGun: Walker's truck in the third book. Originally, Fenella just is very interested in machines and wants to learn to ride it, as well as spend some alone time with Walker. [[spoiler:She later uses it to try and kill the dog, Pierre, to solve the second task - and accidentally crashes it into Leo, which ''does'' complete the second task.]]
* EarnYourHappyEnding: Completing "impossible" tasks definitely qualifies as earning the happy ending.
* EvilDetectingDog: Pierre can smell that Ryland is faerie, rather than a normal cat. He also hides when Padraig visits the house on Lucy's prom night.
* TheFairFolk: There is an entire fae realm that humans are unaware of. The Scarborough curse was created by one of its denizens.
* ForcedTransformation: Ryland is transformed from a manticore to a housecat. He gets used to it, though.
* FreudianExcuse: Padraig is likely half-human, and as an egg was abandoned in a swamp by his mother, who never claimed him as her own and did nothing but mock him as he grew up, along with the other faeries, who called him "The Mud Creature". He initially just wanted companionship.
* GoodGirlsAvoidAbortion: Lucy refuses to abort her baby. Given that this is the case with countless generations before Lucy, it's implied that this trope is a part of the curse to ensure it continues on.
* GoodParents: Soledad and Leo.
* ImpossibleTask: Lucy gets the ones from the song ''Scarborough Fair''. Fenella gets three of her own.
* LawOfInverseFertility: All of the Scarborough women end up pregnant at seventeen, whether they want to or not. In the cases of Miranda and Lucy, at the very least, Padraig interferes to ensure it happens. Meanwhile, according to Miranda's journal, Soledad and Leo were planning on adopting because they wanted a child but couldn't conceive. Subverted in ''Unthinkable'', when Fenella explains that she set out to get pregnant by her fiance to try to dissuade Padraig's romantic advances. She succeeds in getting pregnant, though it doesn't work out as she planned.
* OneWordTitle: Each of the three books: ''Impossible'', ''Extraordinary'', and ''Unthinkable''
* {{Pyromaniac}}: As Fenella becomes interested in technology, she decides to try and solve the first task, destroying safety, by [[spoiler:lighting the house on fire.]] She's later accused of being a pyromaniac for this.
* RapeAsDrama: If the Scarborough women do not become pregnant on their own terms at the age of 17, this happens to them - Lucy included.
* ReasonableAuthorityFigure: Kethalia, in ''Unthinkable''. She is genuinely sympathetic to Fenella and offers to give her the ability to freely travel between the human and faerie realm, to make up for what Padraig did to her. She comes up with a way for Fenella to lose her long life after Fenella makes it clear she wants to die and sends Ryland to help her out.
* RuleOfThree: Lucy and Fenella each receive three tasks. Fenella also has to tell the faerie queen three times that she accepts the challenge before she can be given the tasks.
* ScrewDestiny: Lucy does not intend to go mad like all her ancestors before her.
* SiblingRivalry: The faerie queen Kethalia and her older brother Ryland.
* TeenPregnancy: All the Scarborough girls, at 17.
* TookALevelInKindness: Ryland, by the end of ''Unthinkable''.
* TotallyRadical: 400-year-old Fenella uses "Too much information!", a phrase Lucy had taught her, at one point.
* VictoriousChildhoodFriend: Lucy ends up [[spoiler:marrying Zach]].
* WhamLine: In ''Unthinkable'': [[spoiler:"It turns out the two curses are entangled.". What that means is]]:
--> [[spoiler:Having begun to break the life-curse, you have re-armed the family curse. Now, if you fail to break the life-curse]], the family curse will be reinstated. [[spoiler:Padriag will not have only you, but also the others. Lucy-and the child, Dawn. It will all begin again.]]
* YourDaysAreNumbered: Lucy has 9 months - until the birth of her daughter - to break her curse. Fenella is given three months for her life-curse.