That was the case when Mariska Hargitay shared a photo of her former costar Christopher Meloni on the set of Law & Order: Special Victims Unit during production on its 28th season.

Alongside the selfie, which showed Hargitay, 62, pointing to Meloni, 64, as he stood with his back toward the camera, the actress wrote in a Sept. 22 Instagram post, "Who dat?"

And though Meloni kept quiet when E! News recently asked him about his rumored return to SVU, Hargitay confirmed that her longtime friend will be appearing on the NBC crime drama's 600th episode with another joint selfie, writing, "Happy 600."

The reunion comes five months after Meloni's Law & Order: Organized Crime spinoff—which centered around his character Elliot Stabler's work in New York City's Organized Crime Control Bureau—was canceled following five seasons.

"I wanted to take this moment to thank the fans who not only helped give the character of Elliot Stabler life and longevity, but for sticking with him and welcoming him back," Meloni said in an Instagram video at the time. "I had a great time playing him. It was a great ride, but thank you."

Indeed, Meloni initially turned in Stabler's badge when he ended his 12-year run on SVU in 2011. However, he remained close with Hargitay offscreen over the years, and even reprised his role on the Dick Wolf-created crime procedural several times before launching Organized Crime.

In fact, the Wet Hot American Summer alum recently put their sibling-like bond on display as he shared a picture of himself sniffing Hargitay’s armpit to check for body odor after seeing her star in Every Brilliant Thing on Broadway. 

“Checked out a pal on BWay. Well done @therealmariskahargitay,” Meloni wrote on Instagram June 4. “She brought a freshness to the part- and I know, cuz I double checked- it’s what partners do! Someone needs a Tony to add to their collection.”

Hargitay's awards collection was also the topic of discussion during the 2025 Emmys, when Meloni playfully caught her in a hot mic moment as the two walked by a table of gold statues.

“You’ll never have that,” Hargitay quipped in a September 2025 Instagram video, laughing once she realized he was recording. Meloni then jokingly replied, “You see what I go through? You see what I deal with?”

To see more of Hargitay and Meloni's reunions through the years, read on.

Christopher Meloni and Mariska Hargitay teamed up to present at the 2025 Emmys, where the actress joked to her former costar that he'll "never have" one.

Christopher showed his support for Mariska at the premiere of her 2025 documentary My Mom Jayne.

The two snapped a sweet selfie as they reunited on the set of Law & Order: SVU in March 2025.

In 2021, Mariska and Christopher woke up early to promote a new season of their Law & Order shows on NBC's Today.

Before announcing one of the biggest winners of the night, the 2022 Emmys presenters had a little fun onstage at the Microsoft Theatre. 

The former Law & Order: SVU costars stopped by the Backstage Creations giving suite at the 2022 Emmys, where they have some fun dressing up in their comfortable Spirit Hoods.

"Sunday night dinner," Hargitay shared alongside a selfie of her and Chris, who she starred with on Law & Order: SVU for 12 seasons before the actor left the series in 2011.

Hargitay posed this snap with her bestie while on vacation in December 2018. "Vacay...A great night with this one," she wrote at the time. "#Reunited #OldFriends #PTL."

In May 2018, Meloni and Hargitay hung out together in New York City.

"Crazy ppl on the streets of nyc," Meloni captioned this selfie fail.

You could say 2017 was a blur for these two, as seen in this candid selfie shared during the holidays.

The two pals ran into one another after Thanksgiving in 2017, 

Stabler and Benson finally taking their relationship to the next level? Nope, it's just Meloni planting a friendly kiss on Hargitay.

"Even the effortless moments..." Meloni captioned the previous photo only to follow it up with this funny picture and the caption, "...need to be rehearsed." 

Hargitay shared this sweet snap in honor of her former TV partner's birthday in April 2017 and said "PFL" at the end of the note—because Stabler and Benson are partners for life!

"And then that happened...Just when I thought Valentine's Day was over," Hargitay wrote alongside this kissing picture from Valentine's Day in 2017.

In 2016, the real-life friends celebrated Christmas together.

"Lean on me #PFL #FacialHairDontCare #Hargoatee #HanginWithAFriend #ItsAllInTheEyesKid," Hargitay wrote on this precious picture.

In 2015, in the dark of night, New York City's greatest detectives, err, we mean friends, reunited once again and posed for an epic photo.

In March 2014, the duo reunited for dinner—proving that they will always be partners, even if they aren't acting alongside one another anymore.