Undertow Trilogy Books in Order

The Undertow trilogy is a young adult science-fiction story set after an invasion that changes Coney Island forever. Thousands of ocean-dwelling warriors known as the Alpha have come ashore, and the city responds with fear, barriers, soldiers, and political pressure. The beach community Lyric Walker knows has become a tense border zone.

Lyric has a secret that makes the conflict personal. She is part human and part Sirena, one of the Alpha peoples, and her family has worked hard to keep that fact hidden. She wants to protect the people she loves and survive high school, but neither goal is easy once the Alpha are pushed into public life and human hostility turns violent.

The sea has come to town, and it is not peaceful.

In Undertow, Lyric is drawn into the center of the crisis when she is asked to work with Fathom, an Alpha prince. Their uneasy connection forces her to look past the fear and propaganda surrounding both groups. The books use the invasion setup for action, but they also spend time on divided communities, scapegoating, and the danger of treating whole groups of people as enemies.

The conflict expands in Raging Sea, where Lyric is on the run and searching for her family while the struggle reaches beyond New York. Heart of the Storm brings the central battle to a head as Lyric faces threats from the ocean and from people willing to use fear for power. The plot moves quickly, with sea battles, hidden facilities, shifting alliances, and hard choices.

This is the most intense of Buckley's main series. It has a sharper edge than The Sisters Grimm or NERDS, and Lyric is an older protagonist dealing with anger, grief, loyalty, and an identity that others want to define for her. Begin with Undertow and read straight through, since each book continues the same story.

At its heart, the trilogy asks what happens when a person belongs to more than one world, and both sides demand that she choose.