''Nightshade'' is a paranormal romance trilogy by Andrea Cremer. It has expanded into two prequels and three novellas.

The original trilogy (''Nightshade'', ''Wolfsbane'', and ''Bloodrose'') follows the story of Calla, a young Guardian - a shapeshifter who is able to turn into a wolf. All her life, she's known her place: as a Guardian, her duty - and that of her family and friends - is to protect the Keepers (who are said to have created the Guardians when a wolf saved the life of a Keeper) from their foes, who are known as the Searchers. The war has lasted as long as anyone can remember, and each side has a different story. As part of her duty, Calla is to be mated to another young Guardian, Ren Laroche, on her next birthday, but when she, against the laws of the Keepers, saves the life of a hiker - a teen her age named Shay who, unbeknownst to her, is TheChosenOne destined to ''destroy'' the Keepers - her entire world is turned upside down. A fourth book, ''Snakeroot'', takes place after the main trilogy and features the Searchers Adne and Logan.

The prequels (''Rift'' and ''Rise'') tell the story of how the war between the Keepers and the Searchers originally started. Ember Morrow has known all her life that she is pledged to serve the knights of Conatus beginning at her sixteenth birthday. When the knights realize that one among them is dabbling in dark magic, Ember must choose whether to follow the path of darkness, or to escape the order and pledge her life to destroying her fellow knights.

So far there are three novellas: "Treachery", which is from Calla's brother Ansel's point of view during the events of ''Wolfsbane'', and "Aftermath", which is from the Searchers' point of view after the end of ''Bloodrose'', are two of them. The third, "Shadow Days", is a prequel from Shay's point of view up to the events of the first book, which tied in to a series of puzzles conducted on Facebook as well as a YouTube [[http://www.youtube.com/user/shaydoran mini-series]].

!!Provides Examples of:

* ActionGirl: Nearly every female character has a strong personality and can hold her own in battle.
* AncientOrderOfProtectors: The Guardians (a group of [[VoluntaryShapeshifting wolf shapeshifters]]) have served their masters, the Keepers, for hundreds of years, and one of their most important duties is protecting some mysterious artifacts from their enemies, the Seekers. Subverted when it turns out that the Keepers are really the bad guys and deal with dark magic, and the artifacts are actually pieces of a weapon that TheChosenOne can wield to defeat them. The main character, a Guardian named Calla, eventually helps the Seekers steal them.
* {{Animorphism}}: The Guardians can turn into wolves at will. We later meet other Guardians, who can turn into other animals such as jaguars.
* ArrangedMarriage: The Guardian packs are created and maintained as a result of this - a major plot point in the first book is that Ren and Calla are to be wed and form a new pack.
* AWizardDidIt: The explanation of how they keep their clothes between transformation.
* BadassGay: Mason and Nev, Tess and Lydia in ''Wolfsbane'', Kael and Lukasz in ''Rift''.
* BigBad: Bosque Mar.
* BornIntoSlavery: [[spoiler:The Guardians, though they don't know it's slavery.]]
* [[spoiler:DidNotDieThatWay]]: Ren's mother died when he was a year old. He'd been raised to believe - in fact, all the Guardians believed - that she'd been killed by Searchers. Shay discovers that [[spoiler:the Keepers have been hiding the truth: she'd led a rebellion against the Keepers]], and, [[spoiler:along with all the other Guardians involved in the rebellion, was executed as punishment]].
* DoctorsOrders: After Ember begins to recover from a striga attack, she's ordered to not ride her horse or leave Tearmunn for several days, even though she wishes she could.
* DualWielding: Ember's twin wheel-like blades, Silence and Sorrow.
* FieryRedhead: Ember.
* EmbarrassingNickname: Calla hates being called "Lily".
* HeroicSacrifice: [[spoiler:Ren attacks Emile in order to hold him off long enough to save Calla's father.]]
* InterspeciesRomance: Calla and Shay
* LoveAcrossBattleLines: Shay and Calla, considering that he is [[spoiler: the Scion, who is destined to destroy her masters.]]
* LoveTriangle: Does Calla love Shay or Ren?
* LukeIAmYourFather: [[spoiler:Monroe to Ren.]]
* MentorOccupationalHazard: [[spoiler:Monroe]]
* MentorShip: [[spoiler:Ember and her mentor Barrow end up falling in love.]]
* OurWerewolvesAreDifferent: They're Guardians - they were created as a result of [[spoiler:dark]] magic, and the wolf nature is hereditary on the mother's side. Their blood can heal whoever drinks it, but only if it is offered as a gift.
* {{Prequel}}: ''Rift'' and ''Rise''.
* PropagandaMachine: The Keepers have a very successful one against the Guardians, who are treated horribly but are still loyal.
* ProudScholarRace: The Keepers would like you to think that they are this.
* RescueRomance: Calla and Shay
* SicklyGreenGlow: Bosque Mar's horse's eyes glow with a sickly green light, though it can hide it if need be.
* SignificantBirthdate: {{Invoked}} - Guardian couples mate when the Keepers tell them to, so it was arranged for Calla and Ren to be born on Halloween.
* SlaveRace: Guardians.
* UnexpectedlyAbandoned: In ''Rift'', Conatus is delivered a message that a nearby village is "gone". When they investigate, they find that the buildings are still standing, but nobody's there. [[spoiler:Turns out that Bosque Mar sent wraiths to kill everyone as a "lesson".]]
* VoluntaryShapeshifting: The Guardians turning into wolves. They can even change just part of their body at will, such as changing their teeth into sharp canines when they're angry.