Merry Gentry is the title character of fantasy series by US writer Laurell K. Hamilton, best-known for her previous series Anita Blake: Vampire Hunter. Since 2000, she has been alternating between the two series, publishing 7 Merry Gentry novels as of 2008.
Meredith NicEssus is a faerie princess turned private investigator in a world where faeries are not only known to the general public, but are also fashionable. She takes on the pseudonym "Meredith Gentry" to hide from her family and her past while hiding out in Los Angeles, California as a private investigator at Grey's Detective Agency. Merry, the only Sidhe (pronounced 'shee') royal to be born on American soil, fearing the continuous assassination attempts on her life thinly disguised as duels, flees the Unseelie Court in a final act of self-preservation. Her glamour (the art of magical disguise through illusion) is nearly unrivaled at court, and she is able to pass herself off as a human with fey blood.
The general tone of the writing is less of an outright fantasy and more of an alternate history. The point of divergence from normal history is not provided, although hints are given about how the faerie history intersects with human history (Adolf Hitler, the Irish Potato Famine, and Thomas Jefferson are examples). In the books, Jefferson gave the Unseelie and Seelie courts asylum after the European courts exiled them – however with the caveat that they could not set themselves up as gods or make war on one another, by doing so they would risk being evicted from US soil.
Flash forward to present times. The fey are quite fashionable in the modern United States, and there are many faeriephiles. "Sightings" of the Elven American Princess have covered the tabloids for years now, and Queen Andais' magic is constantly following these false leads--which are becoming more popular than Elvis sightings.
Merry's cousin, Cel, breaks the agreement by which Thomas Jefferson allowed the fey into the United States when he helps a human wizard by the name of Alistair Norton to worship him as a deity by way of a power-draining sex cult which siphons away the power of the women involved, encouraging him to lure fey and sidhe-sided women to his bed. He breaks another of the rules when he gives Norton the use of a magical aphrodisiac known to the courts as Branwyn's Tears (or Fergus' Sweat), which can turn even a sidhe into a sexual slave and melt their glamour. It is the physical and emotional abuse inflicted upon these women which eventually gets the Jeremy Grey Detective Agency involved when his wife and mistress pay the agency a visit together. During a subsequent undercover assignment designed to catch Alistair in the act of breaking the law, Merry is covered in the tears in an attempt to drive her mad with lust when Alistair's seduction techniques fail, and she is outed as the missing Elven American Princess.
At the beginning of the first book in the series, Merry's name full name and title is Princess Meredith NicEssus, Child of Peace, Besaba's Bane. "NicEssus" means, literally, "daughter of Essus"; it is the sort of name given to a child and laid aside once the child has come into his or her powers. That Merry used the name into her thirties is a sign that she is a late bloomer at best, a lesser sidhe at worst. After a child comes into their power, the last name is dropped. later in the series it is revealed that Meredith is a fertility deity whose powers are of both courts.
As of the end of the second book in the series, Merry's name is Meredith, Princess of Flesh and Blood and The Red And White Goddess the demi-fay have given her this name when she gave the wingless demi-fay wings.
The series chronicles the return of Meredith to the Unseelie Court by way of an invitation sent by her Aunt Andais, the Queen of Air and Darkness in the form of her right hand, Doyle, also known as Darkness. She is given men from the queen's own guard, her Ravens, to guard her body and fill her bed as heir to the throne, provided she can conceive a child before her cousin.