O aventură epică plină de acțiune, Godzilla: Regele monștrilor o aduce pe Godzilla într-o confruntare decisivă cu unii dintre cei mai populari monștri din istoria culturii populare. Noua poveste urmează eforturile eroice ale agenției criptozoologice Monarch, în timp ce membrii ei se confruntă cu o serie de monștri de dimensiuni colosale, inclusiv cu Godzilla, care se va confrunta cu Mothra, Rodan și cu rivalul său final, monstrul cu trei capete King Ghidorah. Când aceste super-specii antice, considerate a fi simple mituri, ies la suprafață, toți se luptă pentru supremație, lăsând însăși existența omenirii să atârne în balanță. Oare care va fi soarta omenirii?

Searching for his brother, Ryota stows away on a boat belonging to a criminal alongside two other teenagers. The group shipwrecks on Letchi island and discover the Infant Island natives have been enslaved by a terrorist organization controlling a crustacean monster. Finding a sleeping Godzilla, they decide to awaken him to defeat the terrorists and liberate the natives.

At the turn of the century, all of the Earth's monsters have been rounded up and kept safely on Monsterland. Chaos erupts when a race of she-aliens known as the Kilaaks unleash the monsters across the world.

Journalists Ichiro Sakai and Junko cover the wreckage of a typhoon when an enormous egg is found and claimed by greedy entrepreneurs. Mothra's fairies arrive and are aided by the journalists in a plea for its return. As their requests are denied, Godzilla arises near Nagoya and the people of Infant Island must decide if they are willing to answer Japan's own pleas for help.

Shipwreck survivors found on the presumably uninhabited Infant Island leads to a scientific expedition that discovers a surviving native population along with the Shobijin, tiny twin fairy priestesses of the island's mythical deity called Mothra. After the fairies are kidnapped by an exploitative businessman named Clark Nelson, Mothra sets out to rescue them.

To save the world, Mothra goes back in time in an attempt to defeat a younger King Ghidorah.

A new Mothra takes to the air and battles against Desghidorah to save all of humanity.

The fairies from Infant Island discover a lost city, as well as a giant monster that is attracted to environmental calamities.

A young pilot narrowly escapes the destruction of her home in a stolen ship, only to be followed by the colossal cockroach responsible.