Richard Madden shares his five key secrets to being a successful and Charming prince in “Cinderella.”

It’s hard to fill a prince’s shoes onscreen, but it’s even more difficult fleshing out the famed Prince Charming from the animated 1950 classic Cinderella.

The royal task for Kenneth Branagh’s live-action take fell on Scottish actor Richard Madden — whose royal Robb Stark was gruesomely dispatched in 2013’s “Red Wedding” Game of Thrones episode.

“This search really began and ended with Richard,” says producer Alli Shearmur. “We needed inner strength and emotional intelligence. It’s crucial, since in the original, Prince Charming didn’t even have a last name.”

Here are five keys to Madden’s Prince Charming:

1. Sense of humor

Madden knew that his prince would have to relax his subjects by wielding a disarming sense of humor, which also shows humility and kindness.

“People are going to be nervous to meet him, so he had to have the quality of putting people at ease,” says Madden. “And it shows he can make fun of himself.”

2. Horsemanship

In this version, Prince Charming meets his Cinderella on horseback while hunting — almost performing a dance while circling each other on their steeds.

Madden had riding experience from Game of Thrones, but stepped up the dressage work. He also assisted his less horse-skilled co-star Lily James (Cinderella) who had to ride her steed bareback without reins.

“There was acting there and there was actually trying to stop her horse,” says Madden. “I would go up beside her and yank the horse to a stop. I was literally doing that.”

It looks perfect onscreen, but Madden admits there are outtakes of his horse simply drifting out of the camera shot. And he noticed the crew looked nervous that the horses would bolt through the filming set up. But there were no mishaps.

“I’m lucky to get jobs where I get these amazing film horses that make me look much better than I am,” he charmingly admits.

3. Sword presence

As Game Of Thrones’ Robb Stark, Madden used his sword much more. But the warrior-poet Prince Charming has his sword on his side too.

“He’s a soldier back from the war. It was good to keep that element running through it,” says Madden. “Even if he never felt the need to use it.”

4. Tight pants

This Prince Charming kept the royal britches on the historically correct tight-side, requiring wardrobe specialists to ensure that it did not show too much for Disney’s young audiences.

“You get used to it. But you do feel exposed all the time,” says Madden. “I am not used to wearing such tight trousers.”

5. Dancing

The royal ball is everything in Cinderella. So Madden had to step up his waltz game with lessons four times a week for four months.

“It doesn’t come naturally to me,” says Madden. “It was a mistake to deliberately miss those classes in grammar school. I thought, ‘I’m not good at this so why bother?’ I regretted that the moment I was cast.”

Madden was not even allowed near Cinderella’s actual ball dress until he could prove his dancing skills.

“I went through two practice dresses before they let me near the real one, they wanted to make sure I wouldn’t completely destroy it,” he says. “And I wanted to get it down, so I could focus on my acting and not my feet.”

The work paid off. The waltzing screen smile is real.

“When it finally came down to finally doing the dance, it was actually quite enjoyable,” he says. Charming.

Interviews From 2015