Perhaps Paul Thomas Anderson’s crowning achievement in a filmography filled with fine films, There Will Be Blood is the definitive cinematic portrait of the dark side of the American Dream. An epic in the truest sense, it tells the story of Daniel Plainview, an unscrupulous industrialist who strikes oil during the great oil boom in Southern California at the dawn of the 20th century, bringing out the evil in his soul.

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Daniel Day-Lewis was unsurprisingly awarded the Oscar for Best Actor for his portrayal of Plainview. Making this movie was no easy task, so here are 10 Behind-The-Scenes Facts About There Will Be Blood.

Eli and Paul Sunday weren’t supposed to be twins

Eli Sunday preaching to the crowd in There Will be Blood.

In pre-production on There Will Be Blood, Paul Dano was cast in the small role of Paul Sunday, and another actor (Kel O’Neill) was cast to play Eli Sunday, Paul’s brother, who wasn’t his twin in the original script. However, after Dano shot his only scene in the role of Paul Sunday, Paul Thomas Anderson decided to make the two brothers a pair of identical twins, and asked Dano if he’d be interested in playing Eli, too.

The actor had to start playing Eli, one of the film’s biggest roles, just four days after it was offered to him. By contrast, Daniel Day-Lewis had an entire year to prepare for the role of Daniel Plainview.

The oil derrick fire ruined a shot for No Country for Old Men

Javier Bardem No Country For Old Men

At the 80th Academy Awards, There Will Be Blood and No Country for Old Men tied for the most nominations, with eight each. But this rivalry was going on long before the Oscar ballots were open. Both movies were shooting in Marfa, Texas, at the same time.

When Paul Thomas Anderson and his team were testing out the pyrotechnical effects for the oil derrick fire scene in There Will Be Blood, the smoke that billowed from the flames filled the background of a shot that the Coen brothers were filming for No Country for Old Men, ruining it. The Coens had to delay their production for a whole day to wait for the smoke to clear.

Russell Harvard, who played the adult H.W. Plainview, is deaf in real life

One of the most tragic scenes in There Will Be Blood, H.W. Plainview loses his hearing in a gas blowout. Eli Sunday blames the tragedy on the oil well not being properly blessed. In later scenes, since the movie takes place between 1898 and 1927, we see H.W. as an adult, played by Russell Harvard, who is deaf in real life.

Authentic representation of deaf people, and people with other disabilities, has become an important issue in the film industry, with movies like A Quiet Place and Baby Driver (and, of course, There Will Be Blood) helping to move the needle.

Daniel Plainview’s hats reflect his character development

Daniel Day Lewis in There Will Be Blood

According to costume designer Mark Bridges, the hats that Daniel Plainview wears throughout There Will Be Blood were chosen to reflect his character development. In an interview with the Denver Post, Bridges explained, “Leading up to the first time we see [the main] hat, [Plainview’s] hats kind of echo or inform what’s going on with his career and life.”

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Daniel Day-Lewis also had some input in the selection of Plainview’s hats, as it was his idea for the hats to reflect Plainview’s arc. Bridges also confirmed that the sweat stains on the hats were real, because Day-Lewis wore them all day every day.

A widely circulated on-set photo of Daniel Day-Lewis was actually a photo of someone else

Daniel Day-Lewis in There Will Be Blood

During filming, an on-set photographer took a photo of a man that they believed to be Daniel Day-Lewis. It didn’t look like Day-Lewis, but the photographer thought this was due to changes the actor made to his own appearance. The photo got into the press and was widely circulated around various magazines and websites to show audiences how much Day-Lewis had altered his physical appearance to play the lead role in There Will Be Blood.

It turned out that the man in the photo wasn’t actually Daniel Day-Lewis at all. It was an actor named Vince Froio, who played one of Daniel Plainview’s top associates towards the end of the movie.

Paul Thomas Anderson was heavily inspired by The Treasure of the Sierra Madre

Three men sitting inside a tent and looking serious in The Treasure of Sierra Madre

It’s appropriate that Daniel Day-Lewis partially based Daniel Plainview’s voice and mannerisms on director John Huston, because There Will Be Blood was heavily influenced by Huston’s film The Treasure of the Sierra Madre.

Paul Thomas Anderson has said that rumors of him watching the movie every night during production have been greatly exaggerated, but it did serve as a major inspiration: “What was nice about that movie was that it’s kind of a play wrapped up in the clothes of an adventure film. It’s essentially a dialogue, a dynamic between these three guys. [The film’s] traditional straightforward storytelling was what I was influenced by.”

Some scenes were shot multiple times in different locations

Daniel Day-Lewis in a mine shaft in There Will Be Blood

Writer-director Paul Thomas Anderson wasn’t entirely set on where each scene in There Will Be Blood would take place. So, certain scenes were shot multiple times on different locations, and the results were then evaluated during editing, and the location that worked the best made it into the movie.

During the editing process, Anderson and his team would eat steak with straight vodka every Wednesday night, in order to keep in Daniel Plainview’s mentality while they were piecing together the story of his downfall. Daniel Day-Lewis also immersed himself in Plainview’s mentality, improvising a few scenes and listening to tapes of wealthy tycoons from that era to really nail the voice.

The prop oil was made from the same substance as McDonald’s chocolate milkshakes

There Will Be Blood

Milkshakes are important in There Will Be Blood, because of the infamous “I drink your milkshake!” line. This line was taken straight from an official testimony by New Mexico Republican Senator Albert Fall, who used the milkshake metaphor to explain how he accepted bribes for oil-drilling rights. Paul Thomas Anderson loved the idea that milkshakes were mentioned in such a serious testimony, so he tweaked the monologue slightly and included it in the script.

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As it turns out, the movie has another link to milkshakes. Anderson claims that the prop oil used in the movie contained some of the substance that is used by McDonald’s to make their chocolate milkshakes, which is pretty alarming.

Daniel Day-Lewis appears in all but two scenes

Paul Dano and Daniel Day Lewis in There Will Be Blood

Daniel Day-Lewis appears in almost every scene in There Will Be Blood. There are only two scenes that he doesn’t appear in — the short montage of H.W. Plainview and Mary Sunday leading up to their wedding, and the scene in which a mud-covered Eli Sunday yells at his father — and they’re pretty minor scenes.

Day-Lewis, who is notoriously picky about his projects (and has apparently retired now), accepted the role of Plainview because he’d been a fan of Paul Thomas Anderson’s previous film, Punch-Drunk Love. Anderson was delighted with what Day-Lewis brought to the role, calling his improvised speech in Little Boston “Plainview on a platter.”

The final scene was originally much more graphic

Danie's argument in There Will be Blood

In the final scene of There Will Be Blood, Daniel Plainview chases Eli Sunday around his bowling alley before beating him to death with a bowling pin and declaring, “I’m finished!” In the original script, Plainview beat Eli to death with a tumbler as opposed to a bowling pin, and then he threw Eli’s corpse through the bowling pins and into the cellar below.

However, when the cast and crew were actually on the set, ready to shoot this scene, the graphic content didn’t sit right and the scene was toned down to the version that appears in the final cut.

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