In waters off Infant Island, a presumed uninhabited site for Rolisican atomic tests, the Daini-Gen'you-Maru is caught and run aground in the turbulence of a typhoon.

A rescue party following the storm finds four sailors alive and strangely unafflicted with radiation sickness, which they attribute to the juice provided them by island natives.

The story is broken by tenacious reporter Zenichiro Fukuda and photographer Michi Hanamura, who infiltrate the hospital examining the survivors.

The Rolisican Embassy responds by co-sponsoring a joint Japanese–Rolisican scientific expedition to Infant Island, led by capitalist Clark Nelson.

Chūjō has studied the cultures of islands in the area and ascertained that one of the key hieroglyphs in their written language, a radiant cross-shaped star, translates as Mothra.

There the team discover a vast jungle of mutated flora, a fleeing native tribe, and two young women only twelve inches tall, who save Chujo from being eaten by a vampire plant.

While Nelson profits off a "Secret Fairies Show" in Tokyo featuring the girls singing, both they and the island natives beseech their god Mothra, a giant egg, for help.

Fukuda, Hanamura, and Chūjō communicate with the young women via telepathy; they express conviction that Mothra will come to their aid and warn that "good people are sure to be hurt".

Meanwhile, the island egg hatches to reveal Mothra as a giant caterpillar, who begins swimming the Pacific Ocean toward Japan.

Mothra arrives at the Japanese mainland, impervious to the barrage of weaponry directed at it, and builds a cocoon in the ruins of Tokyo Tower.

He flees incognito to Rolisica with the Shobijin concealed in a suitcase, where Mothra, newly hatched in an imago form, resumes her search.

Nelson attempts to flee the city, but while driving through the streets he is recognized by civilians, and killed in the resultant shootout with police.

Church bells begin to ring, and sunlight illuminates the cross atop the steeple with radiant beams, reminding Chūjō and Hanamura of Mothra's unique symbol and of the girls' voices.

Authors Steve Ryfle and Ed Godziszewski note that Honda treats the film's nuclear anxiety and proxy relationship between America and Japan differently.

They note that Rolisica (an amalgam of Russia and America) is portrayed as a "pushy capitalist superpower" that is more concerned with Nelson's money, allowing his crimes in Japan to go unpunished.

[10] During the summer of 1960, producer Tomoyuki Tanaka hired Shin'ichirō Nakamura to write an original story for a kaiju film.

[15] While writing the original story The Glowing Fairies and Mothra, Nakamura chose a giant moth because he wanted a creature that underwent a transformation.

The smaller eggs hatch caterpillars which turn into moths and fly away, which enrages Ajima to condemn all living things to death and commits suicide by tearing himself into four pieces.

Heartbroken, Ajiko also commits suicide by also tearing herself into four pieces, which turn into four small, immortal fairies dedicated to serving Mothra of the giant glowing egg.

[20] Michiko was originally written as Chujo's assistant and the leader of a protest group that unsuccessfully pressures Nelson to release the Shobijin.

[25] The original story had the Shobijin stand at 60 centimeters but Sekizawa felt the size was too big and would create difficulties when building the sets.

[27] Originally, Mothra was to cocoon herself on the National Diet Building but Sekizawa felt it wasn't "spectacular enough" and changed the setting to Tokyo Tower.

[1] Akira Ifukube was originally given the offer to compose the film but declined, feeling he wasn't confident enough to create music for The Peanuts.

[32] Honda also intended to show how the inhabitants of Infant Island survived a nuclear blast but budget cost forced him to use a bland cave instead.

Haruo Nakajima and Katsumi Tezuka lead members of the special effects art staff inside the suit.

[55] Toho had deemed Mothra's attack on New Kirk City too expensive and advised Honda and Sekizawa to write a more budget friendly climax.

", send two attractive street valley girls in abbreviated space suits through the main business district and school vicinities with signs on their backs reading, "Mothra, the world's most fantastic love story!

"[67] Hazel Flynn of the Los Angeles Citizen News stated, "the sight of the huge flying monster flapping its wings is one of the most impressive special effects I've ever encountered.

"[70] In 2009, the Japanese and American versions of Mothra were released on DVD by Sony Pictures Home Entertainment through their Icons of Sci-fi: Toho Collection set.

[75] According to Toshio Okada, Hayao Miyazaki saw Mothra during its initial release and drew inspiration from it when creating the Nausicaä of the Valley of the Wind manga series.