The live-action 'Mulan' has an unexpected cameo you may overlook the first time around. Here's how it came together.

• Warning: There are massive spoilers ahead for "Mulan."
• Disney's live-action "Mulan" has a big cameo you may have overlooked.
• Keep an eye out for the original film's star, Ming-Na Wen, near the film's end.
• Producer Jason Reed told Insider production needed to work around Wen's "Agents of S.H.I.E.L.D." schedule.
• Cinematographer Mandy Walker told Insider it was meant to be a subtle moment for fans to pick up on.

Disney's live-action "Mulan" is finally available to watch on Disney Plus and there's one huge cameo you may have missed if you weren't looking for it.

Near the film's end, a woman introduces Mulan (Liu Yifei) to the Emperor after she helps save China from Bori Khan (Jason Scott Lee). She's only on screen for a few seconds, and even big Disney fans may not recognize the actress immediately.

The woman, referred to as the "esteemed guest," is played by Ming-Na Wen. Wen voiced Mulan in the original 1998 movie.

"It was quite special because you could hear everybody sort of standing like, 'You know who that is?'" cinematographer Mandy Walker told Insider of filming the subtle cameo.

"She was really lovely and I thought it was a beautiful gesture to have her in the movie," Walker added. "I think that was the idea — not to make it too broad an announcement, but for people to pick up on it."

How Ming-Na Wen's cameo happened in "Mulan"

"Mulan" producer Jason Reed told Insider that he reached out to Wen about doing a cameo in the movie before production started. But it was a logistical nightmare to pull it off.

"Whenever you do something like this it's a great idea until it comes down to actually doing it," he said.

At the time of shooting, Wen was filming the final season of ABC's "Agents of S.H.I.E.L.D," where she plays agent Melinda May. So it took a while to figure out an opening where Wen could jump on a plane from the US and fly to New Zealand to the "Mulan" set for the cameo.

And then the costume design team went into hero mode to get Wen's beautiful costume she has on in the movie ready in time for shooting.

"They worked with the costume fitting for a whole weekend to make it happen," Reed said.

But what made the scene all the more special for Wen is she got to share the experience with her daughter, Michaela.

"After Ming-Na does her introduction, Mulan says something slightly unexpected a few shots later and it cuts to the reaction of someone who gives a 'oh my' reaction. That is Ming-Na Wen's daughter," Reed revealed.

Looking back on it, Reed is very proud Wen is in the movie because he knows what the character means to her.

"This has been a very important part of her life and has been ever since the movie came out," he said. "She's been the face of the movie for a long time and she was super excited to be involved and to come to the set."

Her small role in the movie was so secret that not even the animated movie's co-director, Tony Bancroft, knew about Wen's cameo

"It was so perfect," Bancroft told Insider after the film's premiere in March.

Her appearance was Bancroft's favorite moment of the live-action film, which he praised for paying homage to the original while breaking new ground to stand out from the animated movie.

"Ming-Na was sitting behind us in the screening and I turned around to her and I said, 'You didn't say anything,'" said Bancroft, who brought his daughter along to the premiere. "And she was like, 'Yep, this was my secret.'"

"She kept it a secret the whole time," he added. "It was a total surprise to us that our original Mulan was in the movie. And I was so proud of her too. I just thought it was perfect."

Wen attended the premiere in a multi-colored gown created by her friend, Mark Zunino, who is a red carpet and bridal designer. On Twitter, the actress said she felt like "a glam princess" at the March premiere.

The actress is one of a handful of actors who can say they've played a "Star Wars," Marvel, and Disney character. After voicing Mulan in the 1998 animated movie, Wen played Agent May on "Agents of S.H.I.E.L.D." and most recently joined "The Mandalorian" as the assassin, Fennec Shand.

You can read our review of "Mulan" here.