Emily St. John Mandel’s third novel “Sea of Tranquility” is expansive and complex, sweeping through huge swathes of time and space — from the Canadian wilderness in 1912 to moon colonies in 2401 — as it explores art, human morality and disease. While earlier sections of the novel excel, I was ultimately disappointed by its worldbuilding and character arcs. Nevertheless, “Sea of Tranquility” poses intriguing questions about human nature and the meaning of life over which I found myself ruminating long after finishing the book.

“Sea of Tranquility” is a novel composed of multiple overlapping storylines, marked by four distinct time periods. In 1912, Edwin St. Andrew travels from Britain to Canada, where he lives in exile. In 2020, a woman named Mirella learns of the death of her estranged friend Vincent. In 2203, a novelist named Olive Llewellyn travels from the moon colonies to Earth on a book tour to promote her newly released novel amid a devastating pandemic. In 2401, detective Gaspery Roberts investigates a mysterious anomaly in a Canadian forest that features in the previous three timelines; this anomaly, when witnessed, allows one to momentarily travel through time. Throughout the novel, Gaspery time travels to the past to interview and observe characters from the previous three time periods.

The first section of “Sea of Tranquility” is undeniably the highlight of the novel. Mandel’s quiet, understated prose excels at capturing the quiet wilderness in which Edwin finds himself. In contrast, later sections of the novel falter; Mandel’s description of a futuristic world of moon colonies and holograms is ungrounded and vague. The novel seems needlessly complex in its worldbuilding; it is spread too thin over its timelines and characters. 

The characters of “Sea of Tranquility” also seem vaguely defined, perhaps due to the novel’s large cast size. At times, Mandel seems to gesture towards character complexity, but stops short of actually realizing it. For example, early on in the book, Edwin meets two Indigenous women while on a walk, and has the impulse to assert his opposition to colonization, perhaps out of a sense of guilt. However, he decides to say nothing, the moment passes, and this internal conflict is never explored further.

In another example, Gaspery and his sister Zoey are said to have an emotionally distant relationship; Zoey, in Gaspery’s mind, is elusive and mysterious. It is only at the end of the novel that Gaspery realizes the full extent of his sister’s loneliness and comes to the conclusion that he is “her only person.” Mandel seems to use these brief scenes to methodically prove that these characters are worthy of sympathy. However, the sparsity of these moments, in conjunction with their failure to access the complexity of these characters, renders them unconvincing. Mandel’s characters ultimately lie somewhere between fully fleshed-out people and archetypes: they are given just enough interiority to pass as adequately sympathetic characters, but can’t be considered to have any real depth. 

I wondered whether the novel could have benefited from a smaller cast of characters with further exploration of each. Many of these characters, when taken together, are strangely cohesive — they face similar moral dilemmas and obstacles in life — almost to the point of redundancy. For instance, pandemics feature prominently across all timelines: Edwin dies from the 1918 flu pandemic, Mirella experiences the COVID-19 pandemic and Olive dies from a futuristic disease in the twenty-third century. 

Mandel seems rather self-aware of the abundance of pandemics in her novel. “So I’m guessing I’m not the first to ask you what it’s like to be the author of a pandemic novel during a pandemic,” a journalist, at one point, asks Olive during her book tour.

The book also plays with thematic ties through art. In the twenty-first century, a musician composes a piece based on the anomaly that his sister once saw in a forest. Centuries later, Olive writes a novel that describes a character who listens to that piece in an airship terminal and finds herself transported back to a forest in Canada. In this way, the novel is incredibly recursive: it is very aware of its own form as a book.

Through these intersecting timelines, Mandel raises interesting conundrums about time travel and the value of human life. Zoey warns Gaspery not to attempt to save the lives of the people of the past, in fear that it will compromise the future; she proclaims that “the job requires an almost inhuman level of detachment.” Additionally, multiple characters throughout the novel grapple with the possibility that they are living in a simulation. Gaspery refers to the anomaly as a “corrupted file,” and he ponders the possibility that the world as he knows it is not truly real. This worry is compounded by the fact that, in the book’s futuristic timelines, very little of the characters’ lives, as they see them, are truly real. The humans who inhabit moon colonies live under an artificial sky that is meant to resemble that of the Earth. To communicate across space, characters utilize holograms that give only the appearance of a face-to-face meeting. On a more abstract level, the characters aren’t unfounded in their worry; they are, after all, living in a simulation called a novel.

Ultimately, I found the easy resolutions that the novel poses to these conundrums unconvincing. Gaspery, seemingly without any difficulty at all, resolves to save the people of the past from their fates. He warns Olive to cancel her book tour so that she can avoid contracting a disease that would have resulted in her death. Later on, he warns Edwin not to tell anyone about the anomaly that he experienced in Canada to prevent him from getting committed to an asylum. In the final years of his life, Gaspery comes to the conclusion that whether or not he is living in a simulation simply does not matter, as “a life lived in a simulation is still a life.” Such a conclusion, to me, cheapens the premise of the questions that this novel raises.

“Sea of Tranquility” is certainly an ambitious novel that, through futuristic worldbuilding, raises interesting questions about human nature and the significance of a single human life. However, I found Mandel’s attempts to address these questions to be lackluster and overly simplistic. I’m left unconvinced, ultimately, of whether this novel needs or deserves a neat, easy resolution at all.

Editor’s Note: This article is a review and includes subjective opinions, thoughts and critiques.