|“||Goodbye, old friend||„|
|~ Serizawa's last words.|
Ishiro Serizawa is the main human character from MonsterVerse and the deuteragonist from 2014 film Godzilla and the 2019 film Godzilla: King of the Monsters.
He is portrayed by Ken Watanabe, who also voiced Drift.
In 1999, Serizawa and his assistant Dr. Vivienne Graham are called to the Philippines to investigate a collapsed mine. There, they discover the skeleton of a long-dead member of Godzilla's species along with two giant spores, one of which is hatched.
In the fifteen years following the incident at the Janjira power plant, Serizawa, Graham and a team of Monarch scientists study the male MUTO while it is cocooned and feeding on the plant's reactor. After the MUTO breaks free from its cocoon and destroys Monarch's research facility, Serizawa and Graham are taken aboard the U.S.S. Saratoga to help the U.S. military, under the command of Admiral Willian Stenz, hunt and destroy the MUTO.
After discovering that Godzilla has resurfaced, Serizawa believes that he has risen to kill the MUTO, which was his kind's natural enemy. Serizawa is proven correct when Godzilla swims underneath the Saratoga and confronts the MUTO in Honolulu. After Godzilla and the MUTO both leave Honolulu, Serizawa begins studying the MUTO's echolocation patterns more carefully. Serizawa concludes that the MUTO was communicating with a female—the dormant spore - which at this point was moved to a nuclear waste repository in Nevada. A team of soldiers is sent to the facility in Nevada and discovers that the female has hatched and is attacking Las Vegas.
When the military forms a plan to lure all three monsters offshore and try to kill them with a nuclear warhead, Serizawa protests, claiming that the bomb will have no effect on the monsters and that Godzilla is only there to kill the MUTOs and restore balance. Serizawa's pleas fall on deaf ears however and the military carries out the plan, which fails after the male MUTO steals the armed warhead and delivers it to the female at their nest in the center of San Francisco. After this, Admiral Stenz agrees to Dr. Serizawa's plan to withdraw military effort to destroying the MUTO and let Godzilla handle them. After Stenz refocused military efforts to extracting the bomb, Serizawa tells an extraction team that the MUTOs have likely laid eggs underground and are keeping the warhead there.
After the battle, Serizawa and Graham gather around the seemingly dead body of Godzilla in the ruins of San Francisco. When Godzilla stirs and returns to the ocean, Serizawa looks up in joy as the monster he has dedicated so many years of his life to studying returns to his home in peace.