The Prime Minister seated at his desk in the No 10 Annexe Map Room, May 1945.
The Prime Minister seated at his desk in the No 10 Annexe Map Room, May 1945.

How the Darkest Hour Filmmakers Recreated Winston Churchill’s Secret Underground War Rooms

The Prime Minister seated at his desk in the No 10 Annexe Map Room, May 1945.
The Prime Minister seated at his desk in the No 10 Annexe Map Room, May 1945.

Darkest Hour, the new film starring Gary Oldman as Winston Churchill, shows the iconic leader in some famous places familiar to plenty of Anglophiles and history buffs, locations like 10 Downing Street and the Houses of Parliament. But a portion of the film also takes place in a lesser-seen though just as history-soaked site: a stuffy bunker, the secret underground location of Churchill’s World War II operations from 1940 to 1945.

Today, that bunker is a popular tourist site, Churchill War Rooms (called the Cabinet War Rooms during its use for World War II), part of England's Imperial War Museums.

The Cabinet War Room as it’s seen today within Churchill War Rooms.
The Cabinet War Room as it’s seen today within Churchill War Rooms.

As war dawned and Churchill took the reins after the period of appeasement led by his predecessor Neville Chamberlain, the humble underground government storage space was hurriedly converted into a military information hub. Located underneath the Treasury building in Westminster, it covered about 3 acres and accommodated up to 528 Cabinet and supporting staff members.

The Darkest Hour crew spent three and a half weeks filming scenes that take place in the War Rooms, recreated by production designer Sarah Greenwood and her team at West London’s Ealing Studios.

Greenwood came to Darkest Hour as a longtime collaborator of director Joe Wright (Atonement, Pride & Prejudice). With the exception of 2015’s Pan, she has worked on every feature that Wright’s directed, plus two of his miniseries.

“We argue a lot," Greenwood tells Mental Floss, laughing, of their longtime collaboration. "We’re like siblings, actually. I’m like the older sister. We’ve been together too long.”

Oldman as Churchill, Lily James as Elizabeth Layton (Churchill's secretary) in the Map Room
Gary Oldman and Lily James as Elizabeth Layton, Churchill's secretary, in the recreated Map Room in Darkest Hour (2017).
Focus Features

Wright has spoken about how Greenwood often helpfully challenges his choices, but her plans for the War Rooms were an unusual instance of immediate agreement between the two filmmakers.

“I designed [the War Rooms set], drew up the rough plans and everything over a weekend, and when I showed it to Joe, he was just like—and this is very rare—he was like, ‘Yep, that’s great.’ There were very few changes that we made to that,” Greenwood says. “And I think that came from knowing what it was going to be like. Because we’d been to the real War Rooms, we knew what we were trying to capture.”

Greenwood, along with other members of the art department, visited the Churchill War Rooms about half a dozen times. She remembers being most struck by how apparent it was that this all-important nerve center of war operations was “cobbled together at the 11th hour, [with] furniture brought in from home. There’s this forest of beams from when they brought in a Naval architect to shore the whole thing up when they realized that it was not bombproof.”

The recreated typists' bay of Churchill's War Rooms
The recreated typists' bay, on the set of Darkest Hour at Ealing Studios.
Sarah Greenwood

Greenwood noted the War Rooms’ contrast to the Nazi sites for World War II operations depicted in the 2008 film Valkyrie: “It’s very sharp and organized and clear and cold colors,” she says.

“One of the most important things to understand about the Cabinet War Rooms is they’re an extremely improvised space," Ian Kikuchi, senior curator, Second World War at Imperial War Museums, tells Mental Floss. "The war is not necessarily a surprise, but the War Rooms are not a lavishly purpose-built facility. You can see its kind of lack of bombproof-ness everywhere you go, especially when you look up into the ceiling and you can see the gigantic layer of concrete that they had to add to the ceiling in order to try to improve the protection.”

The closest the War Rooms came to being directly hit was in September 1940, when a bomb fell on Clive Steps, leaving a small crater near what is now the visitor entrance to the site.

The Map Room as it’s seen today within Churchill War Rooms.
The Map Room as it’s seen today within Churchill War Rooms.

“It was a stroke of luck, really, that the War Rooms were never hit,” Kikuchi says. 

The film brought to bustling life a space that Kikuchi and his colleagues are accustomed to seeing frozen in time. 

“It was a real thrill actually," he says. "These corridors that I’m so familiar with—to suddenly see them on the big screen—I was really struck at just how right it all felt.” 

However, Kikuchi did, of course, recognize any deviations from reality that Darkest Hour made with its set, the most noticeable being a rearrangement of the rooms. For example, in the film, the BBC equipment room is right next door to Churchill’s underground bedroom, where he delivered four wartime speeches. At the real site, the equipment that transmitted these speeches is further down the hallway. 

Gary Oldman as Winston Churchill in 'Darkest Hour'
Gary Oldman, as Winston Churchill, delivering a speech at the desk in his bedroom in the Cabinet War Rooms.
Focus Features

Greenwood intentionally took some artistic license with the layout of the War Rooms, creating a more labyrinthine feel, unlike the real-life stretch of rooms along a long corridor. 

Within each room, though, the art department meticulously recreated the environs of that wartime bunker. 

Darkest Hour's Map Room and "Beauty Chorus"
Darkest Hour's Map Room and "beauty chorus."
Sarah Greenwood

Though items from the 1940s tend to be readily available to filmmakers, Darkest Hour’s art department custom-made several props, since the technology and furniture in the War Rooms is so distinctive (and recognizable to the tens of thousands of tourists who visit the site each year). The telephones in the Map Room weren’t a simple, standard black; the so-called “beauty chorus” were bright reds and greens, color-coded and connected to a specific military department or intelligence service. Graphic designer Georgina Millett recreated whole wall-spanning maps specific to the era after several research trips to the British Library. 

The props team also built a replica of the wooden chair that Churchill sat in during tense meetings in the Cabinet Room. On a visit to the War Rooms with fellow cast members, Oldman had the rare privilege of sitting in the very chair from which the iconic leader conducted these meetings. “That’s something that you normally have to be a president or prime minister to get to do,” Kikuchi says. 

The Cabinet Room, at Ealing Studios.
The Cabinet Room, at Ealing Studios.
Sarah Greenwood

Today, on the ends of that chair’s armrests can be seen scratch marks, evoking the nervous energy of its occupant. Close-up shots in Darkest Hour depict Churchill making those gouges with his right-hand fingernails and with the signet ring on his left hand.

Darkest Hour also required some imaginative mystery-solving, alongside the historical research.

“One thing that nobody [among the historical consultants] would ever say, or couldn’t ever give us a real answer on, was whether there were tunnels linking 10 Downing Street to the War Rooms,” Greenwood says. “‘We don’t know' was the answer. I think it’s still a secret actually. I personally think there were tunnels between Downing Street and the Houses of Parliament and everything. But of course, nobody will admit to it.” 

Darkest Hour's switchboard
The War Rooms' switchboard, recreated for Darkest Hour (2017).
Sarah Greenwood

So Greenwood and her team created a dimly-lit set of tunnels stretching from their War Rooms to a small elevator that lifted Churchill back into the famous home of Britain’s Prime Ministers.

Since Darkest Hour takes place over the course of less than a month, beginning in early May 1940, the film doesn’t capture what it was like to spend prolonged amounts of time in the War Rooms. Sleeping in the cramped, rat- and cockroach-infested sub-basement (called “The Dock”), never shown in the film, was a necessity during periods of intense bombing for all but higher-ranking officials (who had bedrooms on the upper levels). Later during the war, 12-hour shifts underground meant that some staff members went weeks without seeing daylight.

Ben Mendelsohn and Gary Oldman in 'Darkest Hour' (2017)
Ben Mendelsohn, as King George VI, with Oldman as Churchill in Darkest Hour (2017).
Jack English/Focus Features

But Wright and cinematographer Bruno Delbonnel still crafted a space with a clear lack of natural lighting, in contrast to the film’s scenes that take place aboveground during daytime, where large, bright beams of sunlight stream into screen versions of 10 Downing Street, the House of Commons, and other historic locations. The stark sunlight also evoked the weather of Churchill’s first month as PM, which was one of the hottest Mays on record. 

Today, the Churchill War Rooms bear an unassuming, modest entrance that’s easy to miss, though it has become an ever-more popular tourist destination since its opening as a museum in 1984. In 2017, the Churchill War Rooms welcomed over half a million visitors, “a number that I’m sure would amaze anyone who ever worked there,” Kikuchi says. 

Map Room Officers at work in the Cabinet War Rooms, 1945.
Map Room Officers at work in the Cabinet War Rooms, 1945.

And as for what Churchill himself—a man who has eloquently written and spoken about the importance of studying history—would think if he could see the Cabinet War Rooms as a popular tourist attraction today? Here’s what Kikuchi had to say: 

“Churchill was a man born in the 1870s. There’s all manner of things about life in the 21st century that he would be amazed and baffled by. Churchill, in his memoirs, he talks about the moment of becoming prime minister, feeling like he was ‘walking with destiny.’ He was a man who was very conscious of his place in history. And I think he would be proud and gratified that his War Rooms still exist and are reminding visitors from around the world of that crisis moment in 1940 that you see dramatized so effectively in Darkest Hour.”

Darkest Hour is in U.S. theaters now and will be released in the UK this Friday. Churchill War Rooms in London is open daily.

The Prime Minister seated at his desk in the No 10 Annexe Map Room, May 1945.
5 Film Transitions Worth Knowing

You see them every day, on TV shows, the news, and in movies, but how well do you know the most oft-used film transitions? Here are the big five:


The dissolve is an editing technique where one clip seems to fade—or dissolve—into the next. As the first clip is fading out, getting lighter and lighter, the second clip starts fading in, becoming more and more prominent. The process usually happens so subtly and so quickly, the viewer isn't even aware of the transition. The above video offers a great overview of the cut, with examples.


This transition is the opposite of the dissolve in that it draws attention to itself. The best example of the wipe is what's known as the Iris Wipe, which you usually find in silent films, like Buster Keaton's or the Merrie Melodies cartoons—the circle getting smaller and smaller. Other wipe shapes include stars, diamonds, and the old turning clock.

The Star Wars films are chock-full of attention-grabbing wipes. Here are two good examples from The Empire Strikes Back. The first shows the clock wipe; the second, the diagonal wipe (pay no attention to the broken blocks at the start of the second clip—that's a technical glitch, not part of the film).


As the name implies, in the basic cutaway, the filmmaker is moving from the action to something else, and then coming back to the action. Cutaways are used to edit out boring shots (like people driving to their destination—why not see what the character is seeing or even thinking sometimes?) or add action to a sequence by changing the pace of the footage. My favorite use of the cutaway is in Family Guy, where the technique is used to insert throwaway gags. Here's a great example:


The L Cut, also called a split edit, is a very cool technique whose name dates back to the old analog film days.

The audio track on a strip of celluloid film runs along the side, near the sprocket holes. In the L Cut transition, the editor traditionally cut the picture frames out of the strip, but left the narrow audio track intact, thus creating an L-shape out of the film. A different camera angle, or scene was then spliced into the spot where the old picture was, so the audio from the old footage was now cut over the new footage.

Of course, with digital editing, one doesn't need to physically cut anything anymore, but the transition is still widely used, and the name has remained the same.

Split edits like these are especially effective in portraying conversations. Imagine how a simple conversation between two people might look if all we ever got was a ping-pong edit back and forth between the two people talking. The L cut allows the viewer to read the emotion on the listener's face, as the dialogue continues over, as we see in this clip from Ferris Bueller's Day Off:


The fade in and fade out usually signal the beginning or end of a scene, especially if the filmmaker is fading to/from black. This is the most common, of course, but fading to white has become trendy, too. The opening title sequence from the HBO series Six Feet Under featured many fades to black and a couple brief fades to white. The very last bit in the sequence fades slowly to white, and is my all-time favorite example of the transition:

The Prime Minister seated at his desk in the No 10 Annexe Map Room, May 1945.
King Features Syndicate
11 Things You Might Not Know About Blondie
King Features Syndicate
King Features Syndicate

For close to 90 years, Chic Young’s comic strip Blondie has been a constant in newspapers around the world, reaching an estimated 280 million readers in 55 countries. Despite its title, most readers are probably more familiar with Blondie’s husband, the sandwich-consuming Dagwood. Check out some facts about the comic’s origins, its feature film franchise, and a very unfortunate incident involving a dirty word that rocked Blondie's readership to its core.


An illustration of Blondie and Dagwood Bumstead of 'Blondie' comics fame
IDW/King Features Syndicate

Before Blondie debuted in 1930, cartoonist Chic Young had attempted to create a female-driven strip without a lot of success. Titles like Beautiful Bab and Dumb Dora were some of the more unfortunate ideas, with Young preoccupied by the notion of having a vapid leading lady. For Blondie, Young initially pursued the “dumb blonde” stereotype before dialing down the chauvinism and allowing the single, mingling Blondie Boopadoop to appear at least as intelligent as the succession of boyfriends courting her in the strip. Later, Blondie would become the voice of reason [PDF] to fiance Dagwood Bumstead’s bumbling presence, inverting the gender roles of Young’s previous strips.


For the debut of Blondie, Young’s syndicate, King Features, launched an aggressive mailing campaign in an effort to entice newspaper editors to pick up the strip. Editors first received a letter “announcing” the engagement of Blondie and Dagwood, which was followed by protestations from the Bumstead family and eventually a cardboard suitcase that cautioned them not to peek inside. Naturally, everyone did. Inside was a paper doll cutout of Blondie wearing lingerie, with her “wardrobe” (more paper doll clothing) included.


He might strike you as incapable of tying his own shoes, but there was a time when Dagwood Bumstead carried real potential. Instead of his current working-stiff incarnation, Dagwood was originally heir to his billionaire father’s railroad fortune. But when he married Blondie in 1933, the Bumstead family effectively disowned him, fearing Blondie was only out for his money. The couple’s move to the middle class was Young’s way of acknowledging the fallout of the Great Depression.


With the Bumstead family highly skeptical of Dagwood’s plans to marry Blondie, the would-be groom decided to earn their blessing by going on a hunger strike that played out in real time. For 28 days, Dagwood refused to eat and grew frail until his family finally consented to the marriage. The narrative stunt drew the attention of new readers, raising Blondie’s profile on the comic pages.


A 'Blondie' comic strip with Blondie and Dagwood Bumstead in bed together
King Features Syndicate

For a good portion of the 20th century, it was seen as proper to depict married couples on television or in comics as sleeping in twin beds, eliminating any hint of carnal activities happening off-screen. (Or in this case, off-panel.) But Young thought this was juvenile and insisted that Blondie and Dagwood appear sleeping in the same double bed. Perhaps not coincidentally, the two had their first child, Alexander, in 1934.


While Blondie and Dagwood got along without incident, the same couldn’t be said for another couple featured in the strip’s early years. One of Blondie’s earlier suitors, Hiho, married girlfriend Betty and the two became supporting characters in the strip. Hiho and Betty had what could be considered a tumultuous relationship, with each threatening to punch out the other on a regular basis [PDF]. Young eventually phased the two out, replacing them with far less volatile Bumstead neighbors Herb and Tootsie Woodley.


After the atomic bomb was dropped twice to bring an end to World War II, American citizens understandably grew skittish about the ramifications of wielding such power. To ease their minds, the U.S. military partnered with Young to produce 1949’s Dagwood Splits the Atom, a “fun” booklet that sees the character shrunk down in size to help readers understand atomic power and nuclear fission. Although other comic characters like Popeye appear, it’s Dagwood who has the honors of blowing a neutron into a uranium atom in order to split it.


Although Young’s son Dean had been working on Blondie and was prepared to take over writing duties when his father passed away in 1973, newspapers weren’t so sure. According to Young, more than 600 papers canceled the strip when his father died, fearing it would suffer a drop in quality. Young persevered and eventually won over the naysayers, reclaiming space in the papers and adding several hundred more. (Currently, Young writes the strip and artist John Marshall illustrates.)


In 1938, with Blondie firmly entrenched on the comics pages, King Features and Young agreed to license the strip to Columbia Pictures for a series of live-action feature films. The movies were shot quickly and economically with stars Penny Singleton and Arthur Lake portraying Blondie and Dagwood, respectively. The studio produced 28 features between 1938 and 1950. Attempts to adapt the comic to television were less successful. A 1954 pilot was unaired, while a 1957 series lasted just one season. Another 13-episode iteration was produced in 1968-69, with Bruce Lee appearing as a karate instructor in the last episode.


With their relatively trivial subject matter, comic strips rarely have the potential to offend. A 2004 Blondie entry proved to be an exception. In the strip, a character uses the word “scumbag” to describe a baseball umpire. Readers wrote in to Dean Young to lodge complaints, with Mr. Young and his proofreaders apparently unaware that “scumbag” is a euphemism for a used prophylactic.


A 2005 'Blondie' comic strip featuring a number of other comic characters
King Features Syndicate

Before shared universes were a thing, Blondie’s 75th anniversary strip published September 4, 2005 had a cameo from virtually every notable comic strip character past and present. As Dagwood and Blondie hold up a cake—shaped like a sandwich, naturally—they’re surrounded by Ziggy, Garfield, Beetle Bailey, Hagar the Horrible, Dilbert, and dozens of others. In the weeks leading up to the strip, the comics pages were full of Blondie references and sight gags.


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