Anthony Fennell, an Irish journalist, arrives in Cape Town to write an article about underwater cable repair ships.

Anthony meets John Conway, the ship's chief of mission, at a colonial-era hotel bar and learns Conway is also Irish.

Conway brings Anthony to his home, where Anthony meets Conway's partner Zanele and is immediately captivated by her.

Flooding in the Congo River triggers an underwater avalanche that severs a fiber-optic cable off the African coast.

Anthony rushes to the port and convinces Conway to let him board the Georges Lecointe despite Conway's repeated warnings.

Anthony endures three days of severe seasickness on the docked ship during a storm but refuses to disembark.

The storm clears and the Georges Lecointe departs for open water; Conway introduces Anthony to the ship's diverse international crew.

With no alcohol available aboard the ship, Anthony achieves sobriety for the first time in nearly two decades.

Conway informs Anthony that a second cable has broken off the coast of Ghana, extending their voyage by several weeks.

After days of trawling the ocean floor, the crew successfully locates and hauls up the broken cable.

A man throws acid at Zanele during her fourth stage performance in London, injuring her; Conway is unable to leave the ship.

Conway vanishes from the Georges Lecointe overnight without informing any crew member or contacting Zanele.

The Georges Lecointe completes the Ghana cable repair and departs; Anthony remains behind in Accra searching for any trace of Conway.

After a long silence, Conway surfaces in Egypt, disables two underwater cables with homemade explosives, and disappears beneath the water.

Anthony visits Zanele in London and together they conclude that Conway wanted to connect the world by disconnecting it.

Irish journalist Anthony Fennell arrives in South Africa to write about underwater cable repair and forges an unlikely bond with John Conway, the enigmatic chief of mission, and Conway's captivating partner Zanele. When flooding triggers an underwater avalanche that severs a cable off the African coast, Anthony convinces Conway to let him join the Georges Lecointe for the repair, enduring seasickness and achieving sobriety along the way. The crew successfully locates and repairs the cable, but news of a brutal acid attack on Zanele and a second cable break in Ghana extends the voyage and visibly destabilizes Conway. On the morning they reach Ghana, Conway vanishes without a trace, leaving Anthony stranded in Accra and searching for answers. After a long silence, Conway resurfaces dramatically in Egypt, sabotaging two underwater cables before disappearing beneath the water, and Anthony eventually reunites with Zanele in London to make sense of everything that happened.

The headline events of the cable repair mission and Conway's unraveling.

Anthony calls the cable company in Brussels and is connected with the ship's chief of mission, John Conway.

After both men agree they dislike the hotel bar, Conway invites Anthony back to his home to continue talking.

Zanele asks Anthony if he has any children, and he lies without understanding why, telling her he does not.

Conway calls Anthony drunk and announces he has resigned from the Georges Lecointe.

Anthony joins Conway's diving group and meets his close friends, a circle of biologists and physicists devoted to the ocean.

Conway describes deep-water free diving to Anthony as an experience like outer space, where he sometimes has to remind himself to surface.

Anthony walks through Cape Town and realizes the entire city has lost internet access, with panicked crowds and cash-only shops.

Crew member Hercules tells Anthony that the ship runs like a family, then casually mentions that Alcoholics Anonymous meetings are held aboard.

Crew member Petrus emerges from the engine room and takes a call on the ship's satellite phone informing him his mother has died.

The Georges Lecointe stops for a half-hour while the entire crew gathers on deck to hold a memorial service and sing a Xhosa funeral song for Petrus.

Anthony begins composing a letter to his teenage son Joli from his ship cabin, hoping to open a path toward reconnection.

While trawling the ocean floor, the crew pulls up a translucent deep-sea octopus; Conway immediately orders it preserved for scientific study.

Anthony searches the internet from his cabin and discovers an old photo of Conway and Zanele in which Conway is labeled with a different first name.

Veliane leads Anthony over a hill into a field of ash where local boys are stripping copper wire from a salvaged segment of underwater cable.

Divers around the world discover backpacks identical to Conway's explosive pack strapped to undersea cables, each found to contain only sand.

While the cable crisis drives the plot forward, a set of smaller events reveals the humanity behind the mission. Anthony's relationship with Conway begins through a Brussels company introduction and deepens during a shore diving excursion where Conway speaks openly about the sea's pull on him. Once aboard the Georges Lecointe, Anthony witnesses the texture of ship life — from a deeply moving memorial service for a crew member's mother to surprising discoveries during the ocean-floor search. In his cabin, cut off from his usual distractions, Anthony begins writing a long-overdue letter to his estranged son Joli. After Conway's disappearance, Anthony's time in Accra is shaped by a quiet friendship with the sharp and perceptive Veliane, and the worldwide discovery of sand-filled backpacks brings Conway's ghost back into the global conversation.

The quieter moments aboard ship and in Accra that reveal character and connection.

Zanele and the children leave for England, and both Conway and Anthony sense the departure will last far longer than six weeks.

Petra, one of Conway's diving friends, hints to Anthony that Conway has unexplained missing years somewhere in his past.

Conway warns Anthony that boarding the Georges Lecointe is a point of no return; Anthony insists on joining him anyway.

Conway tells Anthony that he sees his role as repairing only physical cables, refusing to accept responsibility for restoring the internet's harms.

Anthony recalls how he met his ex-wife Irenea in a hospital waiting room, married her while she was pregnant, and watched her leave for Argentina with their son.

Anthony finds Conway standing alone on deck before dawn, staring silently out at the ocean, surrounded by unmistakable loneliness.

A company publicist asks Anthony to write a promotional article defending the ship's pace, then cancels the request after resolving the dispute herself.

Anthony discovers two crew members secretly looking at a photo of Zanele on a computer; they beg him not to tell Conway.

Conway cuts off Anthony's cabin internet access, which Anthony suspects is deliberate punishment for pressing too hard about Zanele.

Conway reveals he entered the United States illegally, joined the military under a false name, and trained as a combat engineer working with underwater explosives.

Conway admits that Zanele's children are not biologically his, though he has always claimed and loved them as his own.

A naval officer in Accra tells Anthony that Zanele confirmed to police she and Conway were separated before his disappearance.

Anthony drives to a liquor store to celebrate submitting his article but gives his wine away when he unexpectedly encounters Veliane on the street.

In Anthony's fictional reconstruction, Conway dives alone at dawn and secures a thermite explosive to the first cable, successfully severing it.

Zanele tells Anthony that by the time she arrived in England, she and Conway had both already known their relationship was finished.

Beneath the main plot lie the revelations and decisions that slowly expose Conway's true nature and Anthony's hidden wounds. Early signals accumulate quietly — a departure that feels permanent, hints of a shadowy past, and Anthony's suppressed grief over his son — before the voyage even begins in earnest. Aboard the ship, Conway makes a series of choices that betray his deep disillusionment: dismissing the moral value of internet connectivity, severing Anthony's cabin access as a form of control, and ultimately confessing his secret military history and the truth about Zanele's children. The police investigation in Accra confirms the personal fracture at the heart of Conway's disappearance, while Anthony's own decision not to drink marks his quiet but decisive turning point. Anthony's fictional reconstruction of Conway's final dives, paired with Zanele's admission that she and Conway both knew the end had come, together seal the novel's emotional reckoning.

The key decisions, discoveries, and emotional shifts that define who Conway really is.