Freddy left her childhood home in Newhaven 22 years ago and swore never to return. But now her parents are dead and she's back in her hometown to help her brothers manage the family fishmonger.
Nothing here has changed: the stink of fish coming up from the marshes; the shopping trolleys half-buried by muddy tides; the neighbours sniffing for a new piece of gossip. It's not what Freddy would have chosen, but at least while she's here she'll get to see her childhood best friends, Toni and Pauline.
At school, the three of them were inseparable. The teachers called them the Mermaids for their obsession with the sea and with each other. Then Pauline goes missing and Freddy must decide. Go back to her new life, or stay and find her friend?