The German bombing of London and other English cities figures prominently in post-World War II British imagination, as dramatized in Graham Green’s novel “The End of the Affair,” the movie version of “The Lion, The Witch and the Wardrobe,” TV’s “Doctor Who,” and many other cultural examples, including the new feature “Blitz.” 

Directed by Sir Steve McQueen, who helmed the Oscar-winning “12 Years a Slave,” the new Apple TV+ movie focuses on a mother and son during a time of blackouts, underground station shelters, and thousands killed, with the constant bombing central to the narrative. Yet as the story of a family torn apart by war, the picture is unexpectedly uninvolving, owing primarily to the underwritten roles of its chief players. Those are Saoirse Ronan as mother Rita, young actor Elliott Heffernan as son George, and rock singer Paul Weller as Rita’s father.

A born-and-raised Londoner, Mr. McQueen hones in on the diversity of the English capital at the time, with shots incorporating multiple ethnicities as well as moments of racism and xenophobia. George is a biracial 9-year-old, and because much of the film is from his perspective, we see the hardening effects that prejudice and social isolation can have on someone so young. We’re also presented with scenes in which the character encounters more indirect forms of racism and privilege, with the boy examining his own identity, though at times the inspired segments end up simplifying these issues.

The plot is easy to encapsulate: After the family hides out in a tube station during a bombing, Rita decides to send George to live in the country as part of the British government’s plan to evacuate children from the city. At the station, George quarrels with his mum and refuses to say goodbye. While on the train, George regrets his behavior, jumps off, and makes his way back to London and, hopefully, to his mother, despite not knowing the way and the journey’s inherent impediments, the nightly air raids among them.

While George heads back to London and navigates its rubble- and sandbag-strewn streets when he does, we’re also shown how Rita copes with his absence. The young mother works at a munitions factory, and a montage illustrating the building of bombs underscores how women played a key military role in the war. I say “underscore” because the movie is constantly adding emphasis, as if one is listening to an adult reading from a children’s book. Not content with just the montage, Mr. McQueen also has the factory manager give a speech about British soldiers depending on the women’s output.

As the movie progresses, one realizes its overstatements will feature throughout, with the score by Hans Zimmer also pitched too high. Although “Blitz” shares its basic outline with “Empire of the Sun,” and even director Steven Spielberg’s preoccupation with the young, this film rarely applies that master director’s light touch or displays character-based craft in tackling its major set pieces. Instead, we get empty imagery and virtuosity, as in a sequence involving a popular nightclub where the camera pans 360 degrees around the kitchen and dance floor for no discernible reason.

Most of the fault lies in the screenplay written by the director, which rarely evinces originality or detail in its structure or dialogue. Rather than scenes fleshing out George’s daily life at home and in the neighborhood, Mr. McQueen inserts cutesy moments of him singing with his mother and grandfather. Indeed, the movie could be considered almost a musical, with stomping jazz interludes and several original retro ballads. As with most of the movie, the new songs only serve to underline what is readily apparent.  

George’s odyssey to get back to his mother does include some compelling sidelines and side characters, such as his encounter with three young brothers on a freight train and an “Oliver Twist”-like stint with a gang of thieves. These segments, though, can still feel strained and even far-fetched, such as when George meets a Nigerian warden who decides to take the boy on his rounds instead of immediately taking him home. For her part, Rita begins volunteering at a shelter run by an affable little person with communist leanings.

Extensive research went into the story’s look at different aspects of the devastation, yet the movie’s main characters remain ciphers. Ms. Ronan is luminous throughout but unable to give Rita much complexity beyond basic worrying. As George, Mr. Heffernan acquits himself competently if not completely naturally in his first film, failing to fully convince when required to appear in a state of shock, resentful, or dealing with budding adult awareness.

Despite encompassing admirable scope and a few riveting sequences, “Blitz” leaves one unaffected and unscathed in the end.