Emily is a young girl living in the seaside town of Brightport. One day while taking swimming lessons Emily gets a cramp in her legs and has to pull out. Emily wanting to know what happened to her goes for a swim in the ocean the next night and ends up discovering she's a mermaid! After reuniting her human mother and merman father Emily goes on many fantastical adventures with her best friend Shona Silkfin.
There are currently 9 books in the series
- The Tail of Emily Windsnap: Average ordinary girl Emily Windsnap discovers she's a mermaid and goes on a journey to reunite her mom and dad.
- Emily Windsnap and the Monster from the Deep: Emily in a misguided attempt to impress some new mermaid friends unleashes The Kraken and now must find a way to stop it.
- Emily Windsnap and the Castle in the Mist: Emily discovers a mysterious ring that binds itself to her and threatens to turn her either fully human or fully mermaid. Could the Castle in the Mist provide the answer to getting it off?
- Emily Windsnap and the Sirens Secret: A construction project in Brightport could have harmful effects on the nearby mermaid community and Emily and her friends must find a way to stop it.
- Emily Windsnap and the Land of the Midnight Sun: Emily and her boyfriend Aaron are sent on a mission by Neptune himself to the frozen north.
- Emily Windsnap and the Ship of Lost Souls: While on a field trip Emily sees a ghostly ship in the distance. Emily has to save the people onboard before they're lost forever.
- Emily Windsnap and the Falls of Forgotten Island: Shona makes Emily a promise that there will be no more crazy adventures for the next few days while they're on vacation. Emily promises but unfortunately finds herself in the middle of an ancient prophecy anyway.
- Emily Windsnap and the Pirate Prince: While on the way home from vacation the cruise ship Emily is on is attacked by pirates who kidnap Aaron. Emily has to team up with the youngest pirate Sam to get her friend back.
- Emily Windsnap and the Tides of Time: After an adventure-filled vacation Emily is having a hard time readjusting back to normal life. When she gets a chance to make things better with the help of a wishing stone she accidentally makes things terrible for the future.
This book series contains examples of:
- Action Girl: Emily falls into this sometimes.
- Amicable Exes: Emily and Aaron break up at the end of Pirate Prince when they both realize they want different things out of life but promise to stay friends.
- Baffled by Own Biology: When Emily submerges herself in water and swims for the first time during class, she feels what she thinks is her legs numbing and seizing up before she's pulled out of the water, her teacher telling her it's probably a cramp. When she tests herself later, however, she finds this feeling was actually her mermaid tail forming, discovering she's a semi mer. She's also stunned to learn she has a pocket in her tail when her mermaid friend shows her.
- Be Careful What You Wish For: A theme in the 9th book.
- Character Name and the Noun Phrase: Besides the first book, all the books are titled like this.
- Double-Meaning Title: The first book is titled The Tail of Emily Windsnap. While also a play on words with the homophonous word "tale", taken literally, the title makes sense because the book is about Emily first learning about the mermaid world and her connection to it, which of course involves learning that she can grow a tail.
- Half-Human Hybrid: Emily is one as well as Aaron and Mr Beeson. In-Universe they are known as semi mers.
- Happily Married: Despite a few rough patches due to the differences in cultures Emily's mother and father are very happy together.
- Hybrid All Along: The Reveal in the first book is that the reason why Emily transforms into a mermaid when she's submerged in water is because she's half-human, half-merfolk. Such pairings are frowned upon in mer society, to the point that Mr. Beeston kept trying to erase her mother's memory of merfolk.
- I Choose to Stay: In book 7, After the grandfather, he never knew he had effectively dies right in front of him Aaron decides to stay at Forgotten Island because it's his family's ancestral home.
- Interspecies Romance: Emily's mother Mary and Emily's father Jake.
- Kraken and Leviathan: While the Leviathan has yet to show up the Kraken is the centerpiece of book 2.
- Laser-Guided Amnesia: Emily's mother Mary was given a memory-erasing drug to make her forget about her husband Jake when Neptune decreed that human and Mer couples were outlawed. However, being in close proximity to Mer landmarks can bring Mary's memory back which Emily uses to restore her mother's memory.
- Lovable Alpha Bitch: Mandy becomes this after she reconciles with Emily.
- Our Mermaids Are Different: Mermaids in this universe can't change their tails into legs but they can breed with humans and half mermaid half-human hybrids use the Splash method.
- Plot-Mandated Friendship Failure: Emily and Shona have a falling out in Falls of Forgotten Island due to Shona being furious at Emily breaking her "No Adventures" promise but Shona ends up forgiving Emily at the end accepting Emily's adventure-loving nature.
- Thrill Seeker: Emily has shades of this as she notes multiple times she's happiest when she's on an adventure and doesn't feel quite right when things are calm.
- Time Travel: Emily ends up traveling 20 years into the future twice in the 9th book of the series. She ends up seeing the consequences of a wish she made and needs to Set Right What Once Went Wrong.
- The Unmasqued World: The end of Siren's Secret has the existence of merfolk revealed to the people of Brightport in an act of bringing the two communities together.
- Water-Triggered Change: The titular character transforms into a mermaid whenever she's fully submerged in water. The books make a point that she has to be fully submerged, so simply getting wet won't trigger the transformation.
- We Used to Be Friends: Emily used to be friends with Mandy but they had a falling out after Emily got Mandy in trouble with her parents. They reconcile eventually however.
