Prince Harry is full of surprises, including a big one for theatergoers earlier this week.

The Duke of Sussex stunned the audience at an AMC movie theater in California Monday at a screening of his new Netflix five-episode docuseries, "Heart of Invictus," which features a group of injured soldiers as they prepared for last year's Invictus Games in The Netherlands.

Attendee GraceAnn Skidmore shared a selfie with the royal on Instagram.

"Last night I was invited to a special screening of Prince Harry’s new documentary series 'HEART OF INVICTUS,' at AMC CHULA VISTA, CA and got to meet the Duke of Sussex, Harry Himself," Skidmore wrote in the Instagram caption Tuesday. "As a military spouse, USO volunteer, and someone who is passionate about military advocacy this event was one of a kind and I am so thankful for the experience."

Skidmore said, "Harry is every bit as gracious in person as in the media in his mission to support veterans across the world," before thanking the United Service Organizations and Netflix.

"There were lots of cheers and we were so surprised to see Prince Harry coming to spend his evening with us. He stayed the whole screening and even took photos after with some guests," Skidmore said in a statement shared with USA TODAY Thursday. "The experience of seeing this series was special to me not only as the spouse of a service member but also as someone passionate for military advocacy."

Skidmore's friend plus one to the event, Bonnie Pham, also shared video of the royal surprise. Pham joked in the caption that "my friend Harry had to show up and crash the party," quickly adding, "and we’re here for it!!!!!!"

"You guys get to watch it tonight – or at least two episodes – to whet the appetite for the rest of it," Harry said in a video circulated on social media.

The USO also shared a photo of the surprise on social media, including details of the screening for service members from the Navy Wounded Warrior Program. "As a surprise for our service members, Prince Harry, The Duke of Sussex popped in to watch with the audience!"

The USO Instagram post caption quoted Marcus Pace, Veteran and Regional Program Director of the Navy Wounded Warrior Program, Navy Region Southwest, who said, "It was such an honor to sit with the population we serve and watch Heart of Invictus together. It gave us moments of hope, especially knowing many of them are in some of the most difficult times of their lives. But more than anything, it was an evening about community for our wounded warriors and being around other service members going through the same thing."

USA TODAY has reached out to reps at Archewell, the USO, AMC Theatres and Netflix for comment.

How to watch 'Heart of Invictus'

The limited series, which launched Wednesday on the streaming service, from director Orlando von Einsiedel and producer Joanna Natasegara joins the Invictus competitors as they train and prepare for the games.

INVICTUS GAMES 2022:Prince Harry, Duchess Meghan visit with Queen Elizabeth II on their way to Invictus Games

In it, Harry says he didn't have the support he needed when he returned home from combat in Afghanistan as he reached out to other veterans. Talking about post-traumatic stress disorder, Harry said that his return from Afghanistan in 2012 triggered emotions that he suppressed after the death of his mother, Princess Diana, when he was 12 years old. The prince, whose troubles with the royal family have been chronicled in the past, said the impact of Diana's death was never discussed.

"Heart of Invictus" is available to stream now on Netflix.

What are the Invictus Games?

Modeled after the Warrior Games in the United States, Harry founded the Invictus Games in 2014 as a Paralympic-style event designed to inspire military veterans around the world as they work to overcome battlefield injuries.

In 2019, Prince Harry celebrated the fifth anniversary of the first Invictus Games by recalling his words at the opening ceremony as "the worst speech I've ever given."

"I was so nervous, I was shaking," Harry confessed in a video on the now-defunct @Sussexroyal Instagram. He said he remembered his anxiety at seeing the faces of the crowd of chanting competitors arrayed in front of his podium.

He worried about whether anyone would show up, he worried about the weather (it was outdoors), and he worried about his speech. "I knew I had a certain window to be able to get my words out, and we were also running behind. So I rushed it," he chuckled. "It was probably one of the worst speeches I've ever given."

Contributing: Maria Puente, USA TODAY; The Associated Press