Shauna Lawless Returns to Medieval Ireland in Son of the Serpent

Shauna Lawless’s Son of the Serpent arrives in the United States on November 10, 2026, continuing her historical fantasy series Gael Song: Era II. Published by Head of Zeus’s AdAstra imprint, it follows Daughter of the Otherworld into an Ireland threatened by rival powers, immortal enemies and the advance of Anglo-Norman lords.

For readers choosing their next fantasy series, the distinction matters: this is a sequel with an established world behind it. Its immediate starting point is Daughter of the Otherworld, while Lawless’s original Gael Song trilogy offers a longer route into her blend of Irish history and mythology.

What is Son of the Serpent about?

The story opens in winter 1169. Isolde has reached the stronghold of the Descendants, her immortal relatives, but belonging among them is another question. As she develops her magical abilities, disturbing visions complicate her attempts to understand her place in their world.

Elsewhere, Cuan faces dangers that fame cannot solve. His connection to the High King makes him politically vulnerable, while a curse and his feelings for Isolde pull him in competing directions. A stranger’s offer introduces another possible path—and another reason to question whom he can trust.

The premise brings private uncertainty into contact with a wider struggle over Ireland’s future. The publisher describes Irish kingdoms at war while Anglo-Norman lords extend their reach, raising the stakes for clans already divided among themselves.

How it follows Daughter of the Otherworld

The previous novel introduced an especially unsettling problem for Isolde: she reappears more than a century after vanishing, yet her immortal kin cannot explain what happened. Initially believed to possess no magical gift, she enters a world where the Descendants’ ancient enemies, the Fomorians, are seeking greater influence.

Lawless’s description of that first Era II book connects the supernatural conflict with the Norman invasion through the Fomorians’ efforts to manipulate mortal rulers. That makes the new installment’s developing magic part of an existing political struggle.

Based on those premises, the most interesting question is what power will allow Isolde to change—and what it will demand of her. Discovering an ability may make her more capable without making her position more secure.

Where should new readers start?

Read Daughter of the Otherworld before Son of the Serpent. That is our recommendation for following Isolde’s Era II story in order, rather than entering after its central mysteries and relationships have been established.

Readers who prefer the full main-novel publication route can use this order:

Lawless’s author biography identifies the original trilogy and confirms Daughter of the Otherworld as the beginning of Era II. This table covers the main novels; it does not attempt to place the companion novellas.

U.S. release date and edition details

These details follow Bloomsbury’s U.S. listing. Readers who have already seen the book discussed overseas should note the regional difference: Bloomsbury’s UK listing gives September 10, 2026, as its publication date.

Why this release is worth watching

The appeal of the setup is the collision between personal choices and competing claims to power. Isolde needs to understand her abilities; Cuan needs a way through his curse and political exposure. Neither problem exists in isolation from the struggle around them.

For Books of Brilliance readers drawn to historical settings and fantasy politics, that is the reason to investigate Era II. Start with Daughter of the Otherworld to establish the characters, then continue with Son of the Serpent for the next stage of their story.

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