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Fat Man and Little Boy 1989

During World War II, General Leslie Groves, a pragmatic military leader, recruits the brilliant but complex physicist Dr. J. Robert Oppenheimer to develop atomic weapons. The pair embark on a challenging collaboration, racing against time to create the powerful "Fat Man" and the streamlined "Little Boy" bombs. Their differing approaches and personalities create friction, testing their ability to succeed in this top-secret and crucial mission.

During World War II, General Leslie Groves, a pragmatic military leader, recruits the brilliant but complex physicist Dr. J. Robert Oppenheimer to develop atomic weapons. The pair embark on a challenging collaboration, racing against time to create the powerful "Fat Man" and the streamlined "Little Boy" bombs. Their differing approaches and personalities create friction, testing their ability to succeed in this top-secret and crucial mission.

Does Fat Man and Little Boy have end credit scenes?

No!

Fat Man and Little Boy does not have end credit scenes. You can leave when the credits roll.

Meet the Full Cast and Actors of Fat Man and Little Boy

Explore the complete cast of Fat Man and Little Boy, including both lead and supporting actors. Learn who plays each character, discover their past roles and achievements, and find out what makes this ensemble cast stand out in the world of film and television.


Ratings and Reviews for Fat Man and Little Boy

See how Fat Man and Little Boy is rated across major platforms like IMDb, Metacritic, and TMDb. Compare audience scores and critic reviews to understand where Fat Man and Little Boy stands among top-rated movies in its genre.


Metacritic

50

Metascore

6.5

User Score

Rotten Tomatoes
review

50%

TOMATOMETER

review

46%

User Score

IMDb

7.0 /10

IMDb Rating

TMDB

62

%

User Score

Take the Ultimate Fat Man and Little Boy Movie Quiz

Challenge your knowledge of Fat Man and Little Boy with this fun and interactive movie quiz. Test yourself on key plot points, iconic characters, hidden details, and memorable moments to see how well you really know the film.


Fat Man and Little Boy Quiz: A 10‑question quiz testing your knowledge of the 1989 film about the Manhattan Project and the creation of the first atomic bombs.

Who was appointed to oversee the Manhattan Project’s military operations in the film?

Full Plot Summary and Ending Explained for Fat Man and Little Boy

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Read the complete plot summary of Fat Man and Little Boy, including all major events, twists, and the full ending explained in detail. Explore key characters, themes, hidden meanings, and everything you need to understand the story from beginning to end.


In September 1942, the ultra-secret Manhattan Project lands in the hands of Colonel Leslie Groves, a no-nonsense military man who has already earned a reputation for overseeing the construction of the Pentagon. His mission is to outpace Germany in the race to build an atomic weapon, a task that feels almost impossible given the scale and secrecy involved. Groves picks J. Robert Oppenheimer, a brilliant and somewhat enigmatic physicist, to lead the scientific effort. Oppenheimer is drawn to the stark, remote landscape of northern New Mexico, where his family once owned a cabin, and he envisions a research facility that sits atop a mesa near Los Alamos Canyon, northwest of Santa Fe.

From the start, the relationship between Groves and Oppenheimer is defined by clash and compromise. Groves brings order, discipline, and a ruthless focus on schedules, while Oppenheimer, surrounded by a diverse group of scientists, wrestles with the moral and philosophical implications of their work. The scientists debate whether their personal consciences should guide their science or if they must suppress emotion to fulfill a national goal. The project becomes a crucible where professional ambition, ethical concerns, and personal loyalties pull in different directions, and the strain of leadership is felt as much in the offices and laboratories as it is in the field.

Within this high-stakes pressure cooker, individuals grapple with dangerous breakthroughs and the human costs of progress. Nurse Kathleen Robinson and young physicist Michael Merriman become aware that their work may come with consequences that extend far beyond equations and experiments. An accident during a high-risk experiment—an event dubbed Tickling the Dragon’s Tail—leads to a catastrophic exposure for Merriman, who develops grotesque swelling and deformity before his death. The tragedy lays bare the risks of radiation, the fragility of the human body, and the emotional toll on those left behind in the hospital and laboratories.

As the project expands across multiple sites across the United States, security concerns take center stage. Investigations probe possible foreign espionage and internal sympathies, including connections to socialist organizations, heightening paranoia and tension. The scrutiny also touches Oppenheimer personally, revealing that he has had a complicated relationship with Jean Tatlock, who becomes a source of personal and political trouble. Groves orders Oppenheimer to end their relationship, but Oppenheimer’s need to protect secrecy prevents him from fully explaining the reasons, leaving Tatlock to confront heartbreak and a solitary fate.

With the operation sprawling and the clock ticking, the scientists explore two parallel designs to avert a single point of failure. One design targets a large, heavy plutonium bomb that would explode via implosion using shaped charges, known as the “Fat Man.” The other is a leaner, lighter uranium bomb that would be fired in a shotgun-style configuration, nicknamed “Little Boy.” The project moves through technical breakthroughs and stubborn setbacks, testing the limits of engineering, physics, and human resilience.

The narrative culminates at the Trinity Site in the Alamogordo Desert of south-central New Mexico, on a clear July day in 1945. At the moment of detonation, a mushroom cloud rises and the winds roar across the desert as observers feel the profound and humbling awe of witnessing the first atomic explosion. The successful tests of Fat Man and Little Boy propel humanity into a new era—the Atomic Age—while leaving behind a lasting legacy of scientific triumph shadowed by ethical questions, personal losses, and the enduring complexity of discovery under the weight of enormous responsibility.

Uncover the Details: Timeline, Characters, Themes, and Beyond!

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Watch Trailers, Clips & Behind-the-Scenes for Fat Man and Little Boy

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Watch official trailers, exclusive clips, cast interviews, and behind-the-scenes footage from Fat Man and Little Boy. Dive deeper into the making of the film, its standout moments, and key production insights.


Fat Man and Little Boy (1989), 35mm film trailer, scope 2.36:1, 4K trichromy, 3840x1624

Cars Featured in Fat Man and Little Boy

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Explore all cars featured in Fat Man and Little Boy, including their makes, models, scenes they appear in, and their significance to the plot. A must-read for car enthusiasts and movie buffs alike.


Buick

1940

Cadillac

M5 A1 Stuart

Chevrolet

1934

½-Ton

Chrysler

1946

Windsor

Dodge

1939

Luxury Liner

Dodge

1939

Luxury Liner De Luxe

Dodge

M-601

Dodge

Power Wagon

Dodge

unknown

Dodge

unknown

Fat Man and Little Boy Other Names and Titles

Explore the various alternative titles, translations, and other names used for Fat Man and Little Boy across different regions and languages. Understand how the film is marketed and recognized worldwide.


Shadow Makers Creadores De Sombras Fat Man a Little Boy Projekt Manhattan Die Schattenmacher L'ombra di mille soli Creadores de sombras Les Maîtres de l'Ombre Sombras no Futuro Οι Ανθρωποι της Σκιάς יוצרי הצללים Fat Man és Little Boy Создатели тени Tlusťoch a Chlapeček Grăsanul și băiețelul O Início do Fim 胖子与男孩 Gölge Oyuncular 멸망의 창조 Tajna operacija Manhattan I skuggan av en hemlighet Salaisuuksien varjossa

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