London 1885. Linnea Wren lives in defiance of Victorian societal norms, from masquerading as a male groundskeeper at Kew Gardens to expedition leader traveling the world. After a near-death shipwreck, Linnea seizes the opportunity to voyage to Chile and re-establish herself as a naturalist. 
 
But the arduous expedition takes a dark turn. With the assistance of her dangerously attractive and secretive colleague, Matias Ward, Linnea is charged with investigating a grisly ritual murder aboard the ship.
 
Arrival on Chiloé Island brings a temporary respite, but as Linnea and Matias pursue their research and burgeoning relationship, the murderer resumes their violent attacks.
 
Set on the high seas and magical island of Chiloé, Voyage of the Pleiades follows Linnea forging a path outside the confines of 19th-century expectations of women, while navigating a tumultuous relationship under the shadow of murderous threats. Will Linnea and Matias find the culprit or become the next victims?