Godzilla (aka Gojira) is a kaiju (fictional Japanese monster) that has become one of the world's most recognized monsters. He was first seen in the 1954 film Gojira, produced by Toho. To date, Toho has produced 28 Godzilla movies. In 1998, TriStar Pictures produced a remake, set in New York City. The film's name was simply Godzilla; however, the monster that starred in this film (officially known as Zilla) had been completely redesigned and did not closely resemble the original Godzilla.

Godzilla is one of the most recognizable aspects of Japanese popular culture worldwide and remains an important facet of Japanese films, embodying the kaiju subset of the tokusatsu genre. He has been considered a filmographic metaphor for the United States. The earliest Godzilla films, especially the original Gojira, attempted to portray Godzilla as a frightening, nuclear monster. Godzilla represented the fears of many Japanese of a repetition of the nuclear attacks on Hiroshima and Nagasaki. As the series progressed, so did Godzilla himself, changing into a less destructive and more heroic character as the films became increasingly geared towards children. Today, the character has fallen somewhere in the middle, sometimes portrayed as a protector of the Earth (notably Tokyo) from external threats and other times as a bringer of destruction. The usual explanation of his character is that he defends the Earth from other kaiju not because of any liking toward humankind, but because he perceives other monsters as threats to his territory along with natural hostility to other monsters. He is portrayed as an anti-hero.

Godzilla's appearance has changed between films over the years, but many defining details have endured. One detail is his roar that has remained constant. It was first created by combining the song of a whale with a bow being scraped across a cello. In the Japanese films, Godzilla is depicted as a gigantic dinosaur with rough, bumpy charcoal grey scales, a long powerful tail, and bone colored dorsal plates shaped like maple leaves. His origins vary somewhat from film to film, but he is always described as a prehistoric creature, and his first attacks on Japan are linked to the beginning of the Atomic Age. In particular, mutation due to atomic radiation is presented as an explanation for his great size and strange powers. Godzilla's iconic design is composed of a mixture of various species of dinosaurs; specifically, he is based on a Tyrannosaurus, augmented with the dorsal fins of a Stegosaurus and the forelimbs of an Iguanodon.