Three sisters (the eponymous aunts) take care of injured and sick creatures on a tiny island somewhere. They are not becoming any younger, and when, one day, theyre watching a TV show about extinct animals, they suddenly realize that they might go extinct themselves. They need young people to help them and inherit their duties. Therefore, they decide to kidnap kids whom nobody will miss, as the island is top-secret, and just hiring people wont do. (Their niece and nephew are spoiled children, who really wouldnt be able to do hard work; the offspring of a sister who found the island unhygienic and fled as soon as she was an adult.) Etta kidnaps Minette, whose divorced parents are constantly fighting and have her travel from one to the other via train on a regular basis. Coral chooses Fabio, who is originally from Brazil, and is just about to be sent to a horrible English school, where it is implied he will be bullied for looking foreign. Myrtle soon decides that the boy she volunteered to babysit, Lambert, is a horrible child, but when he accidentally sniffs her chloroform, she sees no other solution than to take him to the island and let her sisters sort it out.On the island, Minette and Fabio, after proving themselves by hard work caring for the local fauna, are told about the islands secret: There are magical creatures, too, a family of mermaids, and a boobrie, a giant bird, and others. The aunts try to keep Lambert ignorant, but he manages to phone his father, and thats when things become really difficult for the aunts.
Island of the Aunts contains examples of:
- Break the Haughty: Poor Queeny, after she's caught by Lambert's father.
- Broken Angel: After getting into an oil spill, the mermaids lose their mermaid-typical beauty.
- Broken Bird: Queeny's sister, who had been captured by a sailor for several days before escaping. She is incredibly withdrawn and her voice is still hoarse from crying so much.
- Cold-Blooded Torture: The villains use a family-friendly version of this to get information about the location of magical creatures.
- Dire Beast: The boobrie. A bird of the size of a horse.
- Facial Composite Failure: The police circulate composite drawings of the aunts, who are wanted for kidnapping. However, the descriptions result in grotesque caricatures that look nothing like the real women.
- Gaslighting: A somewhat more benevolent example than most. To keep Lambert from throwing a fit every time he sees one of the mystical animals on the island, Fabio lies to him that none of them actually exist and they're all hallucinations he's having as a side effect of the flour used in their food. Lambert accepts this and copes considerably better while thinking he's just imagining everything.
- The Kindnapper: The aunts are well-meaning, and originally intended to only kidnap kids who wanted to get away from their ordinary lives, anyway. Lambert was an accident.
- Kraken and Leviathan: The giant kraken puts in an appearance. There's a little one, too; it likes cookies and is quite adorable.
- Lima Syndrome: The aunts were never malicious, but they do grow fond of the kids and become a bit more realistic about the whole kidnapping business.
- Stockholm Syndrome: It doesn't take the children long to enjoy living on the island and helping the aunts. It helps that the aunts are considerably more caring than the children's own guardians are. This is lampshaded at one point when Minette asks Fabio if they shouldn't be planning an escape from the island, but they enjoy living there too much to think about running away.
- Never Mess with Granny: Never mess with mermaid granny. The aunts are not actual grandmothers, but still badass, too.
- Our Mermaids Are Different: Of the mermaid family, one is a visibly old lady, and the baby is a merboy, who is rather chubby. Only the young twin mermaids resemble the stereotype.
- Parental Neglect: Minette's parents, towards her. While her mother's boyfriend isn't technically related, we do see him hoping she'll be sent to stay with her father because she takes up too much space in their house.
- Selkies and Wereseals: One of the aunts is friends with a suspiciously intelligent-looking seal. She reads him poetry.
- Shapeshifting Lover: When someone attacks the abovementioned seal, this trope ensues for the aunt who was friends with his seal-form.
- Sirens Are Mermaids: Parodied. A mermaid tried to make money by causing a ship to sink, enchanting the captain with her hypnotizing singing voice... sadly, the times had changed, and instead of gold and treasures, the ship she caused to sink had oil on board.