Planetary romance, also called sword and planet or planetary adventure, is a type of science fiction or science fantasy story. These stories mainly take place on one alien world that is very different from Earth. These worlds often have simple technology and unique physical features and cultures. Some stories are set in the future, where traveling between planets by spaceship is common. Other stories, especially older ones, use different ways to move between planets, like flying carpets or astral projection. In all cases, the main focus is on the exciting adventures that happen on the alien planet, not on how the characters travel between planets.

Prototypes and characteristics

The term "planetary romance" describes a type of story that takes adventure and fantasy traditions from the late 1800s and early 1900s and sets them on other planets. These stories often feature brave heroes exploring exciting, unknown places, such as unmapped areas of South America, Africa, or Asia. Similar stories also took place in ancient or medieval settings, which later influenced the fantasy genre.

In planetary romance, the adventurous spirit of space opera is used to create stories about exploration and discovery. Here, the hero is often a space traveler from Earth, which is compared to modern Western countries and North America—places known for technology and colonialism. Other planets, such as Mars and Venus, take the place of Earth’s distant, exotic regions. Instead of "savage races" or "oriental despotism," these stories often include alien tribes and their rulers. A common theme is "first contact," which explores challenges when different alien civilizations meet and try to communicate.

The term "planetary romance" was first used in 1978 by Russell Letson, who described it in his introduction to a book by Philip José Farmer. The Encyclopedia of Science Fiction explains two rules for using the term. First, if a story is set on an alien world but the world itself has little effect on the plot, like in A Case of Conscience, it is not a planetary romance. Second, stories focused on scientific discovery, such as Mission of Gravity, are not considered planetary romance, even if they include alien planets. Allen Steele notes that "planetary romance" is closely related to "space opera," but they are separate categories.

Early examples in the late 19th and early 20th centuries

In the nineteenth century, early examples of science fiction often took place on Mars. One such work is Across the Zodiac (1880) by Percy Greg, which uses a made-up idea called "apergy" (a type of antigravity) to travel to the Red Planet. An important early work in the genre is Lieut. Gullivar Jones: His Vacation (1905) by Edwin L. Arnold, in which a soldier reaches Mars using a magic carpet and has an adventure with a princess. This idea was later improved upon by Edgar Rice Burroughs. Similar stories include Journey to Mars (1894) and Journey to Venus (1895) by Gustavus W. Pope, both part of his "Romances of the Planets" series.

In the early twentieth century, A Voyage to Arcturus (1920) by David Lindsay is often read more as a philosophical novel than as science fiction. The alien world in the story is mainly used to explore deep ideas and themes.

Edgar Rice Burroughs and "sword and planet" stories

Edgar Rice Burroughs was the first writer to share stories of this kind with a large audience. His first Barsoom (Mars) stories were published in the pulp magazine The All-Story in 1912.

Burroughs’s Barsoom is filled with a wide variety of cultures and advanced technologies, which are common in classic planetary romance stories. Some of the futuristic inventions in the setting include the "radium engine" and aircraft that use the "eighth ray" to stay airborne. The world includes Martian cavalry and a social system led by emperors and princesses.

The Barsoom stories are full of exciting adventures, such as duels, battles in arenas, narrow escapes, and fights with dangerous creatures. Because of these elements, these works are often described as "sword and planet" stories.

These novels are part of both science fiction and fantasy genres. However, magical or supernatural elements are rarely included or are explained within the story. For example, in A Princess of Mars, telepathy is used to control machines, and religious groups or gods are shown to be based on misunderstandings or false beliefs.

The Dune series by Frank Herbert and Star Wars by George Lucas both use a mix of futuristic and medieval-like elements, such as knightly groups, royal families, and codes of honor, combined with technology.

Because of Burroughs’s success, many other writers followed his style. Otis Adelbert Kline, for example, wrote the Grandon of Venus trilogy and the Swordsman of Mars series, which used similar adventurous planetary romance themes. Burroughs later returned to the idea with his Carson of Venus series in the 1930s. In 2007, the American publisher Paizo started the Planet Stories imprint to reprint classic science fantasy and planetary romance works, including new editions of Kline’s Martian novels.

The pulps and the codification of the form (1926–1939)

In 1926, the launch of Amazing Stories started a new market for science fiction stories about adventures on other planets. This market grew larger during the 1930s.

One magazine that focused only on space adventures was Planet Stories, which began in 1939. Around the same time, Startling Stories debuted as a companion magazine to Thrilling Wonder Stories. It featured one complete novel in each issue. Meanwhile, older magazines like Weird Tales had always mixed stories about strange science and mystery with traditional fantasy and horror.

C. L. Moore was a key writer in this style. Her series about the adventurer Northwest Smith began with the story "Shambleau," published in Weird Tales in November 1933. In her stories, action takes a back seat to psychological tension and the mix of fear and curiosity about the unknown, often including themes of attraction.

Robert E. Howard wrote "Almuric" in 1939, a three-part novel set on an alien planet with tribal societies and harsh conditions. The story focuses on physical challenges and survival, showing a hero from Earth proving strength in a strange, primitive world.

Stanley G. Weinbaum wrote "A Martian Odyssey" in 1934, often seen as an early example of planetary romance. His story presents Mars not just as a strange setting but as a place where humans meet beings very different from themselves. Weinbaum described these aliens with attention to their biology and culture, showing ideas that would later become central to the genre.

1940s and 1950s: consolidation and maturation

During the 1940s and 1950s, Leigh Brackett made an important contribution to the planetary romance genre. She often wrote stories for magazines like Planet Stories and Thrilling Wonder Stories. Her stories focused on controlled, adventure-filled tales set on a Mars similar to the one created by Edgar Rice Burroughs. Three short novels in the Eric John Stark series appeared in Planet Stories: The Secret of Sinharat (originally titled Queen of the Martian Catacombs, published in 1949), People of the Talisman (originally Black Amazon of Mars, published in 1951), and Enchantress of Venus (published in 1949).

At the same time, Startling Stories published important works. In August 1952, Philip José Farmer wrote The Lovers, which was later expanded into a full book in 1961. This story explored themes of love and alien life and earned Farmer the 1953 Hugo Award for "most promising new writer." In September 1952, Jack Vance published Big Planet, a story that became a model for planetary romance. It described a large world with few metals, leading to societies that use simple technology. Many of Vance’s later science fiction stories, such as Showboat World (1975), the Alastor Cluster trilogy, the Durdane trilogy, and the Tschai sequence, also fit this genre.

Murray Leinster, an author active from the 1930s to the 1950s, wrote The Forgotten Planet (1954), which combined stories originally published between 1920 and 1953. Around the same time, C. S. Lewis wrote his Space Trilogy, which includes Out of the Silent Planet (1938), Perelandra (1943), and That Hideous Strength (1945).

In 1958, Tom Godwin wrote The Survivors, a story about 4,000 human colonists left to survive on a cold, harsh world. Murray Leinster’s The Forgotten Planet (1954) tells the story of a small group of humans who struggle on a world only partly made suitable for life. The first two chapters of this book were published as separate stories in 1920 and 1921.

• Cover of Planet Stories, Fall 1947.
• Cover of the comic-book magazine Planet Comics, January 1945.

From the 1960s onward

Starting in the mid-1960s, stories about planets in our solar system became less popular as space exploration showed that nearby planets were harsh and empty. This change was especially clear after the 1965 Mariner 4 images of Mars, which changed how people and writers saw the planet. At the same time, many writers began setting their stories on planets outside our solar system, using ideas like faster-than-light travel to explain space journeys.

One exception was the long series Tarnsman of Gor by John Norman, which began in 1966. This story is set on a planet called Counter-Earth, which shares Earth’s orbit but is located on the opposite side of the Sun near a point called the L3 point. The idea of Counter-Earth has problems from a scientific perspective, but it was accepted in the subgenre of stories like these.

At the same time, writers began creating stories that clearly looked back at older styles of planetary romance. Lin Carter started the Callisto series in 1972, which was inspired by Edgar Rice Burroughs’ stories about Mars. Michael Moorcock, writing under the name Edward P. Bradbury, created a Martian trilogy featuring a character named Kane. Around the same time, Kenneth Bulmer, writing as Alan Burt Akers, started the Dray Prescot series, which was set on a planet called Kregen and clearly copied the style of Burroughs’ work. These stories were published for many years by DAW Books and later continued in German translations.

Another type of planetary romance focuses on detailed descriptions of alien worlds. The Krishna series by L. Sprague de Camp, part of a larger setting called Viagens Interplanetarias, takes place on planets with societies that are technologically simple. The stories describe these societies’ traditions, governments, and cultures in detail, as if the human characters are studying them like scientists.

Several large science fiction series are often considered examples of planetary romance. These include the Darkover series by Marion Zimmer Bradley, which began in 1958, and the Dragonriders of Pern series by Anne McCaffrey, which started in 1967. In 1985, critic David Pringle called Bradley and McCaffrey two of the most important writers of planetary romance at that time.

The Dune series by Frank Herbert, which began in 1963, includes many elements of planetary romance but also explores political, religious, and environmental themes. Herbert originally planned to set his story on Mars but chose an imaginary planet instead. Dune is often called the best science fiction novel ever written and is one of the most popular books worldwide. It was listed in the BBC’s 2019 collection of 100 novels that shaped the world and is credited with helping science fiction explore more complex ideas.

Early works in Ursula K. Le Guin’s Hainish universe, such as Rocannon’s World and Planet of Exile (both from 1966), are set on alien planets.

Other stories that fit the planetary romance category include Planet of the Apes by Pierre Boulle, which was published in 1963. This book uses a fictional world where apes are the dominant species to examine human society and its myths. Similar stories include Planet of the Damned and Planet of No Return by Harry Harrison, which explore themes of colonization and power.

In the 1970s and 1980s, new stories expanded the ideas of planetary romance. Larry Niven’s Ringworld (1970) features a massive artificial structure that acts like a planet, with different regions, cultures, and dangers. Robert Silverberg’s Majipoor Chronicles (1982) includes stories set on a richly imagined world. Brian Aldiss’s Helliconia trilogy (1982–1985) follows a planet with extremely long seasons that shape its history and society.

In the early 1990s, French author Ayerdhal wrote the Mytale trilogy (1991), which focused on detailed and exotic worldbuilding. Around the same time, Kim Stanley Robinson’s Mars trilogy (1992–1996) explored the colonization and transformation of Mars, mixing science with ideas about politics and society. Catherine Asaro’s Skolian Empire series (starting in 1995) combined stories about alien worlds with elements of romance and family history.

Today, planetary romance is a major part of science fiction, even though few writers use that term to describe their work. Because planetary romance and space opera often mix together, it can be hard to tell them apart in many stories.

Comics

In comics, interplanetary adventure became a major theme, with Flash Gordon by Alex Raymond, which began as a newspaper strip in 1934, serving as a key example. Critics consider it one of the earliest influences in science fiction comics and compare it to the stories of Edgar Rice Burroughs, helping to shape a long-lasting image of adventure on distant worlds.

In the United States, Planet Comics (1940–1953), a comic book linked to the pulp magazine Planet Stories, focused on interplanetary adventure. It is described as containing mostly "planetary romances" set within the Solar System.

In Italy, an early example is S.K.1 by Guido Moroni Celsi, a comic strip for Topolino that began in 1935. This story is often seen as a space opera heavily influenced by, and similar to, Flash Gordon. Many scholars classify it as "fantasy," even though it is part of science fiction.

During the postwar years and the Silver Age, the idea of adventure on other worlds was updated in Adam Strange (1958, DC Comics). This story is often described as clearly inspired by John Carter of Mars: a human archaeologist is transported to the planet Rann in the Alpha Centauri system.

A planetary story reimagined for families is Space Family Robinson, published by Gold Key Comics in 1963. It shares many similarities with the later TV series Lost in Space (1965–1968). Both were loosely based on The Swiss Family Robinson (1812) by Johann David Wyss, a classic example of the "robinsonade" genre.

In the 1970s, the tradition blended with fantasy in long-running independent comics like Elfquest (1978) by Wendy and Richard Pini. Set on the "World of Two Moons," this story takes place on a planet with a native human population and elves and trolls descended from alien ancestors. This science-fiction premise forms the basis of a narrative style similar to high fantasy.

Filmography

A list of films and TV series that focus on adventure and survival on one alien world.

• Aelita (1924), directed by Yakov Protazanov. One of the earliest films set on Mars, it includes stories of political conflict and adventure on the Red Planet. It also inspired the style of the Flash Gordon series, especially its costumes and settings.
• Flash Gordon (1936), based on a comic strip by Alex Raymond. This film serial introduced the idea of space adventures, including journeys to the planet Mongo, battles between rival groups, and scenes that became a common model for similar stories.
• Planet of Storms (1962), based on a book by Alexander Kazantsev and directed by Pavel Klushantsev. A Soviet film about a space mission to Venus, it includes exploration of the planet’s surface, dangerous environments, and alien creatures.
• Barbarella (1968), directed by Roger Vadim. Adapted from a comic by Jean-Claude Forest, it features space adventures on alien planets, with futuristic cities and powers. It helped shape a popular style of space-themed storytelling.
• Fantastic Planet (1973), directed by René Laloux. An animated film set entirely on the alien world Ygam, it explores relationships between different species and the development of ecosystems and native cultures.
• Flash Gordon (1980), directed by Mike Hodges. A colorful and exaggerated version of space adventures, featuring exotic planets, alien rulers, and challenges on the planet Mongo.
• Dune (1984), directed by David Lynch. Based on the novel by Frank Herbert, it follows events on the desert planet Arrakis, where the planet’s resources, culture, and environment play a central role in the story.
• Gor (1987), directed by Fritz Kiersch. Based on a book by John Norman, it is set on a planet called Counter-Earth, where city-states, social classes, and warrior traditions shape the story. A sequel, Outlaw of Gor (1988), was also made.
• Earth 2 (1994–1995), a TV series. It follows a small group of people living on a planet called G-889, exploring themes like survival, colonization, and interactions with an alien environment.
• Pitch Black (2000), directed by David Twohy. A survival story on an alien planet, where people stranded after a crash must fight dangerous creatures that avoid light. Though it includes horror elements, it shares similarities with space adventure stories.
• Frank Herbert's Dune (2000), a TV miniseries. It adapts the first book in the Dune series, focusing on the planet Arrakis and how its environment, politics, and conflicts drive the story.
• Frank Herbert's Children of Dune (2003), a TV miniseries. A sequel to the Dune series, it continues the story of Arrakis, expanding on its history and the challenges faced by its people.
• Flash Gordon (2007–2008), a TV series. Inspired by the comic strip, it updates the space adventure theme, including travel between Earth and the planet Mongo and conflicts between different groups.
• Avatar (2009), directed by James Cameron. A story about a space mission to the planet Pandora, it includes detailed worldbuilding and a conflict between humans and the planet’s native people.
• John Carter (2012), directed by Andrew Stanton. Based on a classic science fiction novel, it takes place on the planet Barsoom, featuring cities, battles, and alien cultures.
• Valerian and the City of a Thousand Planets (2017), directed by Luc Besson. Adapted from a French comic, it tells a story of space exploration in a universe with many species and cultures.
• Annihilation (2018), directed by Alex Garland. Based on a novel, it follows a group exploring a mysterious area on an alien planet called "the Shimmer," where strange ecosystems and biology drive the story.
• Dune: Part One (2021), directed by Denis Villeneuve. An adaptation of the first part of the Dune novel, it focuses on the planet Arrakis, showing how its environment and resources shape the plot.
• After Blue (Paradis sale) (2021), directed by Bertrand Mandico. A story about a journey on a planet where only women live, with the plot following a series of events and encounters.
• Avatar: The Way of Water (2022), directed by James Cameron. A continuation of the Avatar story, it keeps the focus on the alien planet Pandora and its people.
• Scavengers Reign (2023), an animated series. It takes place mostly on the planet Vesta, where the environment and life cycles influence the story.
• Dune: Part Two (2024), directed by Denis Villeneuve. The second part of the Dune adaptation, it continues the story on Arrakis, showing more war, adventure, and conflicts between groups.