H. G. Wells's The War of the Worlds is a novel that was labeled “scientific romance” in its day. Its plot centers on the arrival of Martians, who are running out of resources on their own planet and have come to conquer earth. Wells draws heavily on a scientific perspective as his narrator joins a group of scientists who observe a disturbance on Mars and then inspect the alien cylinders that fall in the narrator's neighborhood. Most of those scientists fail to escape when the Martians shoot off their heat ray. The narrator exits just in time.

The tale is also a “romance” in the sense that it narrates a spectacular adventure in which the main character and his companions struggle to survive against great odds. This is “romance” in the older definition of the word, as in the medieval romances that relate the fantastic adventures of brave knights.

Many people today would call The War of the Worlds “science fiction,” although that genre did not exist when the novel was first published in 1898. That said, though, the book did inspire many imitations and can be said to be a forerunner or even a pioneer of the science fiction genre.

Scholars also point out that the book contains elements of several other genres, including horror (Martians killing everything in sight and causing terror throughout the country), adventure (the narrator's escape from the Martians with plenty of tight spots and near failures), and war drama (as the soldiers battle the Martians).