In Depression-era Los Angeles, Guy Gabaldon gets into a fight at school when another boy snitches about his breaking into a grocery store. After Japanese-American Kaz Uni learns that Guy's mother is in the hospital and his father is dead, he invites Guy to stay with his family. As Kaz's parents speak little English, Guy begins to learn Japanese. Then, when Guy's mother dies, the Unis adopt him. He becomes especially close to Kaz's mother. After the attack on Pearl Harbor and the US entry into World War II, Gabaldon's foster family is sent to an internment camp: Camp Manzanar. Gabaldon is drafted, but fails his physical exam due to a perforated eardrum. When Gabaldon goes to visit the Unis, he learns that George and Kaz have been allowed to join the Army and are fighting in Italy with the 442nd Regimental Combat Team. After making sure that "mama-san" does not object, he manages to enlist in the Marines on the strength of his language skills. Gabaldon does not make a good first impression on Platoon Sgt. Bill Hazen at Camp Pendleton, but wins him over. When they are shipped to Hawaii to join the Regimental Intelligence section of the 2nd Marines, 2nd Marine Division, he gets himself, Hazen and Cpl. Pete Lewis bottles of whiskey and dates with two Japanese-American women and standoffish reporter Sheila Lincoln. Sheila is disgusted by the behavior of the rowdy Marines, but eventually warms up to Gabaldon after a few drinks. Going ashore on Saipan, he freezes at first when he comes under fire for the first time, but regains his composure. He uses his Japanese language skills to persuade Japanese soldiers to surrender. In fighting against a banzai charge, Lewis is killed, and later during the bloody campaign for the island, Hazen is shot in the leg and then killed by a Japanese swordsman. Gabaldon then gets mad, stops talking Japanese soldiers into surrender and starts killing them ruthlessly. After he sees two civilians kill themselves rather than surrender, he remembers George and "mama-san" and changes back to the way he was. During the final battle, he convinces the Japanese general to order approximately 1000 Japanese soldiers and 500 civilians to surrender.
Gramercy Pictures bought the screen rights of Gabaldon's story in June 1957. Previously, it had been featured on the TV show This Is Your Life. Phil Karlson called it "one of the most important pictures that I may ever make because it was the true story of the Nisei, what happened in this country. But Allied Artists, even at that point, looked at it as a great war story that you could make for a price. They had no idea what I was doing." The film was shot on location in Okinawa.
A worthwhile novelization of the screenplay was written by American writer Edward S. Aarons, published in a mass market, tie-in paperback edition under the Gold Medal Books imprint, with 1960 copyright assigned to Fawcett Publications. The book's presentation falls under the category of "implied novelization," as there is no attribution anywhere to the screenplay, the screenstory or their respective authors, and the front cover action illustration of two soldiers only suggests star Jeffrey Hunter in the foreground; however the back cover contains, along with brief descriptive info, a romantic still from the movie and a blurb about the film, naming the studio, the production company and the stars. Even these indicia were removed, however, with the release of a second printing, probably a year or two later. Save for the uptick in price, the front cover illustration is identical, but the back cover is white, displaying only the brief descriptive info and the symbol of the U.S. Marine Corps. Implications of the film as source material were no doubt obliterated from the book to make the most out of the by-line, as Aarons was one of Gold Medal's most popular authors, and would remain so until the end of his career.