Melissa McCarthy reveals the 'Little Mermaid' switch that 'changed the game' for Ursula

Melissa McCarthy knew she had big tentacles to fill portraying villainous Ursula for the live-action “The Little Mermaid.”

McCarthy fell hard for the outrageously coiffed, half-octopus sea witch of the 1989 Disney animated original while working as a nanny for two VHS-obsessed children.

"I've seen 'The Little Mermaid' more than any other movie, hundreds of times. We literally watched it every night," says McCarthy, 52. "I've always thought Ursula was the dishiest, most incredible part."

Playing the dream role in the remake (in theaters Friday) alongside Halle Bailey's mermaid Ariel proved doubly challenging for two-time Oscar nominee McCarthy - not only pulling off a convincingly conniving performance featuring Ursula's big song, "Poor Unfortunate Souls," but inevitably inviting comparisons to her beloved original animated Ursula, voiced by Pat Carroll.

"My hope was to give all the love I have for Pat Carroll's original," says McCarthy. "And then put my own spin on it."

Here's how McCarthy spun her Ursula in "The Little Mermaid":

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Melissa McCarthy proved she had the vocal chops for 'Poor Unfortunate Souls'

Portraying Disney's new Ursula − who tricks Ariel into giving up her golden voice for human legs and feet to pursue her true love, Prince Eric − proved to be one of the hottest casting stories in Hollywood. Even Lizzo threw her blond Ursula wig in the ring in 2018, dressing in a full ensemble and belting "Poor Unfortunate Souls" in a social media video. McCarthy implored director Rob Marshall in what she was sure was a futile effort.

"I told him, 'I'm probably not even on the bottom of your list. But I would love to talk to you about it, please, because I feel this Ursula connection,' " says McCarthy.

Over lunch, Marshall told McCarthy he was already aware of her singing chops from Barbra Streisand's 2016 album "Encore: Movie Partners Sing Broadway," which features the unlikely duo singing "Anything You Can Do."

The Streisand song helped. "But I didn't really know to what extent Melissa could sing," says Marshall. "I was thrilled to see that she literally has this massive voice with so many colors. And she's fearless."

"We just clicked as friends and collaborators," McCarthy says of Marshall.

Even Lizzo came around on the casting after meeting McCarthy at the taping of Adele’s “One Night Only” concert special and bonding over their shared love for Ursula. "I'm definitely watching 'Little Mermaid' this weekend," Lizzo told USA TODAY.

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McCarthy has had decades to consider, and sympathize with, Ursula's plight. Sure, she fools innocent Ariel, and the sea witch is a scourge to King Triton (Javier Bardem). But she's got her reasons. After all, Ursula lives alone at the sea's bottom with only two eel henchmen, Flotsam and Jetsam.

"She's categorized as the villain, but I have a complicated view of Ursula. She's misunderstood, damaged," says McCarthy, who became more Ursula-compassionate during the COVID-19 pandemic that interrupted filming. "Coming out of lockdown to play someone who is not at 100% mental health because of her isolation − we can all relate to that."

To boot, there's a new twist to Ursula's dastardly power move to dethrone King Triton and become Queen of Atlantica. In the new version, the two characters are related. So Triton kicked his own sister from the kingdom.

"To know that your family banished you and sent you into exile, that changed the game for me," says McCarthy. "The very people she wants to love have thrown her aside. Even if she deserved it, she's missed out on her whole life."

Empathy only goes so far, however, as McCarthy brings delicious badness to Ursula. She capped the performance by singing "Poor Unfortunate Souls" with a 200-piece orchestra. "That's as terrifying as singing with Barbra Streisand," says McCarthy.

Melissa McCarthy gave up her Ursula wig, learned to swim like 'a creature who lives in the water'

The underwater "Little Mermaid" scenes were shot in a studio against a blue screen that required McCarthy to be strapped into rigs to simulate effortless water movement. The water and special effects, like Ursula's hair and tentacles, were added digitally through computer graphics. But the levitating movements were very real.

"I had to go to 'swim school' because Rob really wanted it to appear that you're not swimming, but sort of floating like a creature who lives in the water," says McCarthy, who perfected her water "slither" for Ursula. "I've never seen that kind of beautiful, nonsymmetrical underwater movement in a movie."

Shooting with blue-screen technology meant that McCarthy had to wear a skull cap rather than Ursula's famed white hair. This was "at first, traumatic" for McCarthy, who had grown to love the Ursula wig she had worn since a transformative camera test.

"Once I had put that wig on, it felt like 'Oh, darling,' like everything made sense with Ursula," says McCarthy. "I had quite a few conversations with Rob, asking, 'Can I wear the wig anyway?' "

Request denied. But McCarthy was able to lean into Ursula's elaborate makeup, which took more than an hour each day to apply, and her gloriously dark aubergine fingernails.

"I can't imagine finding my Ursula without that makeup, it's the armor she puts on to show the world," says McCarthy.

The corset dress with iridescent tendrils popping from the collar was the crowning piece. McCarthy worked with costume designer Colleen Atwood to ensure maximum flexibility for the water scenes. "Colleen designed a corset that still allowed me to slither," says McCarthy.

Seeing the final performance after all the laborious computer-generated image additions − from Ursula's tentacles to her fabulous hair − was breathtaking.

"Every single hair was drawn and manipulated through a series of computer movements. It just looked incredible," says McCarthy, who fully understood the no-wig edict when she saw Ursula's marvelous mane on screen. "It was like, 'I get it! I really get it.' "

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This article originally appeared on USA TODAY: Melissa McCarthy plays Ursula without a wig in 'Little Mermaid.' Why?