The Rival Submarines

In Short

This is a classic adventure novel centered on the early days of submarine warfare. It follows Sub-Lieutenant Arnold Hythe, who is drawn into the orbit of Captain Restronguet, an enigmatic inventor operating a vessel far more advanced than those of the British Navy. As they hunt a piratical rival, Karl von Harburg, who is impersonating Restronguet to provoke a war between great powers, the story balances technical wonder with the moral complexities of modern combat. It remains a quintessential example of the "techno-thriller" genre at the dawn of the twentieth century.

The Story

The story opens in the tense atmosphere of 1917, where the British Navy is baffled by the antics of Captain Restronguet, a man who proves his submarine's superiority by depositing dummy mines in protected naval harbors. Sub-Lieutenant Arnold Hythe is assigned to investigate these mysteries but soon finds himself a passenger—and eventually a participant—aboard Restronguet’s vessel, the Aphrodite. Restronguet is a brilliant but reclusive Englishman who considers submarine warfare a "despicable form of destruction" yet uses his own superior craft to uphold a personal code of honor.

The central conflict arises from the actions of Karl von Harburg, a former associate of Restronguet who has turned pirate. Von Harburg is deliberately attacking merchant and naval vessels while masquerading as Restronguet, hoping to incite a catastrophic war between Britain and Germany. Restronguet, determined to dissociate himself from these atrocities and protect the British Empire, vows to hunt down and destroy von Harburg’s submarine, the Vorwartz. Their pursuit takes them across the globe, from the English Channel to the Mediterranean and eventually the Zambezi River in Africa.

Along the way, the crew of the Aphrodite navigates treacherous waters, survives a violent lightning strike that nearly kills the captain, and engages in an uneasy alliance with the owner of an airship, the Pride of Rhodesia. As they close in on von Harburg, they discover he has fled into a shallow river system where he cannot submerge, leaving him vulnerable. In a climactic sequence, the Aphrodite and the airship corner the pirate vessel. Following the final confrontation, a weary and disillusioned Restronguet abandons his ship, leaving it for Hythe to return to the British authorities. The book concludes with Hythe delivering the Aphrodite to the Admiralty, fulfilling its creator's secret desire to see the powerful craft serve his country, even as the man himself vanishes into obscurity.

How It Unfolds

The mystery of the intruder The British Navy discovers that a strange, unidentified vessel is repeatedly breaching their defenses at Portsmouth and Cherbourg with impunity. Sub-Lieutenant Hythe is tasked with tracking the craft, which leads him directly into the hands of the elusive Captain Restronguet.

The code of the captain Hythe is taken aboard the Aphrodite as a sort of reluctant guest, where he learns that his captor is an Englishman dedicated to stopping a madman. They set off on a global chase to find the pirate von Harburg, who has been committing acts of war under a false identity.

Navigating the elements The pursuit is punctuated by technical and natural hazards, including a terrifying encounter with a submarine volcano and a lightning strike that nearly claims the captain’s life. Hythe gradually earns the trust of the crew, becoming a key figure in their operations.

The final pursuit The hunt moves to the African coast, where the rivals converge in the Zambezi River. With the help of an airship commander, the Aphrodite traps the pirate and eliminates the threat to international peace.

The transition of power Realizing his work is finished and his vow to never surrender his ship to the government has been met by his own design, Restronguet disappears. Hythe takes command of the Aphrodite and sails it back to England to deliver it to the Admiralty.

The People

Sub-Lieutenant Arnold Hythe is the reader's eyes, a dutiful naval officer whose skepticism of the Aphrodite evolves into profound professional respect. He serves as the moral compass, constantly struggling to balance his orders from the Admiralty with his growing admiration for Restronguet.

Captain John Restronguet is the archetype of the gentleman-genius. He is a man of rigid contradictions: a pacifist who constructs the most lethal weapon of his era, and a patriot who refuses to work for the government while quietly serving its interests. His eventual decision to "vanish" is the final act of a man who values his independence above all else.

Karl von Harburg stands as the dark reflection of Restronguet. Driven by personal grudges and a desire for global chaos, he is a villain devoid of the code of honor that defines the protagonist. His character serves as a warning of what happens when advanced technology falls into the hands of those who harbor no moral constraints.

Captain Jones, the owner of the airship Pride of Rhodesia, brings a youthful, competitive energy to the narrative. He represents the new age of aerial warfare, acting as a foil to the submarine-focused world of the other men.

In Its Own Voice

"And with one touch of my little finger I could do more damage, and without being seen, to that place yonder than the combined aerial fleets of Germany and Austria."

Restronguet demonstrates the terrifying capability of his vessel to a shocked Hythe during their initial voyage.

"Better by far to place no limitations and make war so horrible that no nation will dare draw the sword; or else restrict the weapons of offence to solid armour-piercing shells for naval warfare, small calibre rifle bullets and cold steel."

Restronguet outlines his grim philosophy on the nature of international conflict and the futility of halfway measures in the Geneva Convention.

What It's Really About

The central argument of the book concerns the double-edged nature of technological progress in warfare. Through the lens of the "restronium"-plated Aphrodite, the story examines how new inventions force nations into an arms race that makes conflict increasingly impersonal and "despicable." The book grapples with the tension between individual honor and state duty, suggesting that the most powerful tools of destruction are safest when controlled by individuals who possess a moral code, rather than by governments motivated by fear or expansion. Ultimately, it is a meditation on the idea that true peace might only be achieved when war becomes so horrific that its tools are discarded entirely, leaving humanity to rely on "cold steel" rather than mechanical annihilation.

Why Read It Today

Readers who enjoy early twentieth-century naval history, or those fascinated by the "mad scientist" tropes that preceded modern science fiction, will find much to admire here. The book captures a specific, ephemeral moment in history when the submarine was still a new and terrifying "miracle" of engineering, and the fear of "air-invasion" was just beginning to take hold in the public imagination.

The prose is straightforward and brisk, reflecting the maritime traditions of the era. However, modern readers should be prepared for the period-specific attitudes, particularly regarding the depiction of international relations and the colonial context of the search in Africa. There is also a fair amount of nautical jargon that grounds the story in a very real, very technical sense of the sea. If you are interested in the evolution of the techno-thriller, this book provides a fascinating look at the genre’s roots. It is less a character study and more an exploration of how the world feels when the rules of combat are suddenly, irrevocably broken by a single, hidden vessel. You are left with the lingering, haunting image of a man who builds a world-changing machine only to realize the world is not yet ready to control it.