How actors like Christian Bale became unrecognizable onscreen

Actors who undergo major transformations are a staple of award-season chatter, and this year is no exception. We’ve heard a great deal of it already: Did you recognize Tilda Swinton under all that old-man makeup? How did Rami Malek manage to speak coherently while sporting such large fake teeth? Just how many pounds did Christian Bale put on to play a certain calculating politician? And so on.

But no matter how talented an actor is, they never go it alone. Among those who help them physically embody their characters are often prosthetic and makeup artists, hair stylists, vocal coaches and, of course, directors.

In honor of the Golden Globe Awards, which air Sunday night on NBC, here’s a closer look at how several nominated actors — plus a couple others — transformed for the big screen.

John C. Reilly, “Stan & Ollie”

In getting ready to play Oliver Hardy, half of the world’s most famous comedy duo, Reilly referred to one of the funnyman’s nicknames: Babe.

“He was called Babe because he looked like a chubby little baby from the time he was a chubby little baby to the time he was a grown man,” Reilly said. “I got inspired by the name and said, ‘Let’s look at what some fat babies look like.’ “

So he donned a fat suit, carrying weight as a baby’s body does, and Oscar-winning makeup artist Mark Coulier used prosthetics to turn his features into Hardy’s. It took three hours for Reilly to transform each morning, and another to take it all off at the end of the day.

“Mark was such a great painter, I couldn’t tell where my skin was and where the piece was unless I felt it,” the actor said.

Bradley Cooper, “A Star Is Born”

As his own director, Cooper had the benefit of being able to portray Jackson Maine exactly as he saw fit. That included growing out his hair and beard; hiring Oscar-winning makeup artist Ve Neill to give him spray tans, darken his beard and make his eyes bloodshot for drunk scenes, as she told Vulture; and working with vocal coach Tim Monich to perfect the country-rocker’s gravelly voice and twangy, not “too country” accent.

“It hurt my esophagus. I would have pain for the first couple of months,” Cooper told The Washington Post in the fall. “It’s not only lowering your voice, it’s speaking different rhythmically.”

Charlize Theron, “Tully”

Theron has transformed before, most memorably for her Oscar-winning turn in 2003’s “Monster.” For “Tully,” in which she portrays a beleaguered mother of three young children, Theron turned to potato chips — which she had in her car, in her kitchen, in her trailer, even in her bathroom — to help her gain close to 50 pounds.

“What they say about ‘what you eat is who you are’ is so true, because I ate like a person who just didn’t move, and I felt like that,” she said on “The Ellen Show” in April. “I was lethargic and tired all the time, and that was a hard thing to break. Because it’s more mental than it is almost physical.”

Rosamund Pike, “A Private War”

Pike, an English actress, spent a year preparing for her role as late war correspondent Marie Colvin in “A Private War.” She worked with a dialect coach to drop her voice an octave and adopt a Long Island accent, according to director Matthew Heineman, and spent months with a dance coach to learn how to move and carry herself as Marie did — holding tension in her neck and splaying her hands when she gesticulated, for example.

Designer Denise Kum helped with Pike’s makeup, hair and prosthetics.

“It was remarkable to see how (Pike) turned into this woman who didn’t obviously look or sound at all like her,” Heineman said, later adding: “I was very astounded and blown away by Ros’ performance.”

Christian Bale, “Vice”

Bale frequently changes his weight to play different characters — as Trevor Reznik in “The Machinist,” he shrank to just 120 pounds. But to play Dick Cheney in “Vice,” Bale instead gained 40 pounds, by “eating a lot of pies” and, according to a recent piece published in the New York Times, wore fleshy prosthetics created using an identical mold of his head. After makeup, the actor bore features such as the former vice president’s nose, his chin dimple and deep creases running from his nose to his jowls.

“He put on the suit, walked into the office with all of us, and everybody just died,” prosthetics and makeup effect designer Greg Cannom told the Times. “I was just shocked. He looked just like him.”

Margot Robbie, “Mary Queen of Scots”

How do you make such a modern beauty look like a smallpox-suffering Queen Elizabeth I? A prosthetic nose and boils, an array of wigs and a whole bunch of makeup. “Mary Queen of Scots” features at least five stages of the 16th-century monarch’s evolution — what British makeup artist Jenny Shircore called her “fresh and pretty stage” to her balding, pancake makeup stage. For Shircore to accomplish the latter, Robbie would sit in the makeup chair for three hours.

“Jealousy and fear between the two women was about power, and they were both very aware of each other’s beauty,” Shircore told The Post in December, referring to the queen’s rivalry with her cousin Mary. “When Elizabeth was losing her beauty because of the smallpox scarring, she harnessed what was left with makeup.”

Nicole Kidman, “Destroyer”

In “Destroyer,” Kidman plays a Los Angeles police detective who went undercover with a criminal gang years ago but is now, as director Karyn Kusama told Vanity Fair, a “middle-aged woman with a past that she wears on her face.” This translated to makeup that displayed the effects of sun damage, sleep deprivation, stress and anger.

Kidman doesn’t undergo extensive transformations as often as some of her peers do, according to Kusama, who added that the actress would rather be on the set than in the makeup chair. So they kept the makeup application process short, but still ended up with a character who looks as though she “wears her ugliness on the outside, all that smallness and bitterness.”

Rami Malek, “Bohemian Rhapsody”

What stands out most about Malek’s version of Freddie Mercury might be his large teeth. Makeup, hair and prosthetics designer Jan Sewell had originally asked a teeth specialist to create a prosthetic set comparable in size to the Queen frontman’s, according to Variety, but that overwhelmed Malek’s face. So it was scaled down.

The actor’s jawline was already as strong as Mercury’s, Sewell told the trade outlet, but his eyes were too far apart. So they tacked on a prosthetic nose that “pulled Rami’s eyes together” and finished the looks with fake mustaches and a variety of wigs.

Tilda Swinton, “Suspiria”

Remember Mark Coulier, the makeup artist from “Stan & Ollie”? He’s back.

Swinton and director Luca Guadagnino long denied rumors that she was actually Lutz Ebersdorf, an “actor” who had been photographed in full costume and makeup during “Suspiria’s” production, and whom they both insisted played the elderly male psychoanalyst Dr. Josef Klemperer, one of the only men in the film.

But in October, Swinton came clean to the New York Times about Lutz’s true identity, and Coulier revealed how he made Swinton and her “very feminine bone structure” seem more masculine. They committed to the bit.

“She had this nice, weighty set of genitalia,” Coulier said. “She managed to get it out on set on a couple of occasions.”