James Gunn Engaged to Peacemaker Star Jennifer Holland — See the Ring!

JAMES GUNN/ INSTAGRAM James Gunn and Jennifer Holland

James Gunn and Jennifer Holland are engaged!

The filmmaker, 55, and actress — who stars in Peacemaker, created by Gunn — are set to tie the knot, he announced on Instagram Sunday.

Gunn simply wrote "😏❤️" in the caption of his announcement, which featured a photo of Holland, 35, sipping from a mug amid a mountainous backdrop, a diamond ring visible on her left hand.

Well wishes poured in from fellow stars, like Peacemaker actor Steve Agee's "❤️❤️ love you both!"

"😮 YOU GUYS! 😍," said Wil Wheaton, while Suicide Squad's Viola Davis chimed in, "Aaaaaaaahhh!!!!! Congratulations!!!!!" and Guardians of the Galaxy franchise star Karen Gillan added, "OMG!!!!!!!😍❤️😍❤️😍❤️

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Holland and Gunn have been in a relationship since 2015, when they were first introduced by their mutual friend Michael Rosenbaum. The Chicago-born actress later appeared in the Gunn-produced 2019 superhero horror film Brightburn.

Holland joined the DCEU with last year's The Suicide Squad, which was written and directed by Gunn. She originated the onscreen role of Emilia Harcourt, an A.R.G.U.S. agent assisting the rag-tag group of supers through their mission from the comms room.

Last week, Holland told PEOPLE that working on Peacemaker, in which she reprises her role as Harcourt, brought her and Gunn "closer" as a couple.

"It was great. We had an absolutely amazing time. At the end of it, our personal relationship was closer for the experience," she said. "We got really lucky in that we work really well together and it just works for us."

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In Peacemaker, Harcourt is part of the black ops team working on "Project Butterfly," fighting against the parasitic butterfly-like alien species that's begun taking human form.

She butts heads with the eponymous vigilante (John Cena), but the penultimate episode saw the entire team (which includes Danielle Brooks, Freddie Stroma and Agee, 52) come together to save the day in last week's season 1 finale.

Of her initial role in The Suicide Squad, Holland told PEOPLE, "I had no expectations that it was going to go any further than that. It was just, 'I'm going to do this fun thing with James and have a great time for a couple of weeks.' That's kind of what we thought it was going to be. Then the pandemic hit, James got bored while he was doing post-production on The Suicide Squad and he ended up writing this series."

"When he first started writing it, he had absolutely no idea that Emilia was going to be such an integral part of the story," she added. "The way his writing flows, he just lets the story take him where it needs to go. She became a very integral part of the story. I'm just so grateful for it because it's all an absolute dream for me."