Everett is an introverted, solitary man whose life spans from an orphaned childhood in 1908 to living off the grid in the woods outside Saint John during the Great Depression. He carries deep psychological scars from serving in the First World War in place of his brother. His life changes dramatically when he discovers an abandoned baby in the woods and decides to protect the child from those hunting her.

Known to her friends as Jake, Jacinda is a trained dendrologist (tree scientist) working as a tour guide at a luxury island resort following a catastrophic environmental collapse known as the Great Withering. Carrying crushing student debt, she struggles with anxiety about her future and the health of the island's remaining old-growth trees. She remains disconnected from her biological family history until her ex-fiancé arrives with a startling legal claim.

Willow is a fiercely independent environmental activist who actively protests the timber industry her family built. Traveling the country in a van, she engages in direct sabotage against logging equipment, resulting in frequent clashes with the law. She drops out of Yale to pursue her activism, creating immense friction between her and her father.

Harris is the blind, highly successful founder of the Greenwood Timber Company. Orphaned in a train crash and raised alongside Everett, he utilizes his early educational advantages to build a ruthless business empire. He operates with strict pragmatism, conducting highly profitable but morally questionable international timber deals in the years leading up to the Second World War.

Liam is a skilled custom carpenter who uses reclaimed wood to build high-end residential projects. He grew up resenting his mother's nomadic, anti-establishment lifestyle, longing for permanence and stability. After overcoming an addiction to oxycodone triggered by a previous injury, he struggles with deep insecurities that affect his romantic relationships.

Lomax is a physically massive debt collector and enforcer for the Holtcorp industrial empire. Suffering from severe chronic joint pain, he relies on opium-laced cigars and later laudanum to function. He operates with an intense desire to distance himself from his working-class roots and his father's history of addiction, though the pressure of his job consistently undermines these efforts.

Holt is a wealthy, ruthless industrialist struggling to maintain his corporate empire during the Great Depression. Unforgiving and highly concerned with his public reputation, he employs a small army of enforcers and detectives to clean up his personal scandals. He demands absolute loyalty and results from his staff.

Feeney is a sharp-witted, irreverent Irish poet hired to travel with Harris Greenwood to Japan. Tasked with serving as a "describer" for the blind tycoon, he translates the visual world into striking language. He refuses to cater to Harris's arrogance, establishing a dynamic of honesty that quickly evolves into a deep, secret romantic bond.

Temple is an independent, resourceful woman running a struggling dirt farm in Estevan. Following a series of personal tragedies, she maintains a charitable tradition of housing unhoused workers and transforms an old church on her property into a vast community library. She offers Everett temporary shelter in exchange for him planting maple trees to serve as a windbreak.

Meena is a fiercely dedicated violinist based in Los Angeles. She values her independence and career above all else, frequently traveling to play loaned instruments. Her relationship with Liam fractures because she refuses to compromise her autonomy to satisfy his deep need for traditional domestic stability.

Silas is Jacinda's former fiancé who abandoned his studies in biology to become a corporate lawyer. He arrives at the Arboreal Cathedral to present Jacinda with a historical diary and a legal theory that could entitle her to the Holtcorp fortune and ownership of the island.

Euphemia is a former employee of R.J. Holt who becomes pregnant during the Great Depression. Fearing Holt's plans to take the child, she flees his estate with a sensitive diary that documents his abuse and affairs. Her decision to run sets off a massive cross-country manhunt.

Knut is a Forest Guide at the Greenwood Arboreal Cathedral. He shares Jacinda's genuine reverence for the island's ecology and her disdain for the wealthy tourists and opportunistic guides who treat the site as a mere stepping stone for their careers.

Davidoff is the stressed supervisor of the Forest Guides at the Cathedral. Heavily reliant on his salary to pay for his daughters' medical treatments, he strictly enforces Holtcorp's rules and refuses to acknowledge the ecological sickness spreading through the island to avoid bad publicity.

Mort Baumgartner is the loyal, practical assistant to Harris Greenwood. He helps manage the vast logistics of the Greenwood Timber Company and travels with Harris to arrange complex international negotiations.

Art McSorley is a seasoned railroad detective hired by R.J. Holt to take over the search for Everett when Lomax's expenses mount. He operates methodically, leaning on local authorities and informants to track his targets.

Fiona Craig is a Scottish immigrant who isolates herself from the town after her physician husband dies of tuberculosis. She allows the newly orphaned Everett and Harris to roam her property, quietly accepting the gifts they craft for her without ever inviting them inside.

Gertie is an elderly cook working on Temple Van Horne's farm. Formerly unhoused, she was taken in by Temple and remains fiercely loyal to her employer during both dust storms and police raids.

Lavern is the stressed wife of Harvey Bennett Lomax. She remains in Saint John to care for their seven children, frequently suffering the consequences of Holt's financial threats while her husband is away on assignments.

Howard Blank is an old acquaintance of Everett Greenwood who operates on the fringes of the law. He initially connects Everett with a shady potential adoptive family before attempting to sell information to Lomax for reward money.