Mariska Hargitay and Christopher Meloni on Their Long-Standing Friendship and TV Reunion

More than 21 years after the first episode of Law & Order: Special Victims Unit premiered, Mariska Hargitay and Christopher Meloni still "have each other's back."

The actors costarred on the series for 12 years as detective duo Olivia Benson and Elliot Stabler, before Meloni left in 2011 due to issues with contract negotiations. Through it all, however, they have remained close friends and will soon reunite onscreen for an episode of SVU, airing right before the premiere of spinoff Law & Order: Organized Crime, in which Stabler is the central character.

Ahead of the new series, premiering April 1 on NBC, Hargitay, 57, and Meloni, 59, are reminiscing on their immediate connection and lasting friendship.

"It happened at the screen test," Meloni tells PEOPLE of their initial meeting in this week's cover story, explaining that they both "walked into the screen test, me telling her a story, and we get up onstage in front of all the suits, and we're just so engaged."

For much more on Mariska Hargitay and Christopher Meloni, pick up this week's issue, on newsstands Friday, or subscribe here.

Ruven Afanador

Hargitay also felt an instant bond. "I walked in, saw him, and I went, 'That guy. That's the guy.' It went deep, very fast. We both knew that it was something big," she recalls. "I won't say that I fully understood it, but I knew that meeting him was important and life-changing. My father, my husband, [Law & Order creator] Dick Wolf and Chris are the four pillar men in my life. And that happened early."

While viewers were breathlessly watching them onscreen for the first 12 seasons of SVU, the stars were bearing witness to each other's major life milestones offscreen, from the loss of Hargitay's dad, actor Mickey Hargitay, to becoming parents themselves.

Chris Haston/NBC/Getty

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Meloni had a front-row seat as Hargitay found love with actor Peter Hermann, 53, whom she first met when he had a guest-starring role on SVU. The two have now been married for 16 years and are parents to August, 14, and Amaya and Andrew, both 9.

As for Meloni, he was already married to his wife, artist Sherman Williams, 61, when SVU began. When the couple welcomed Sophia, now 19, in 2001 (they later had son Dante, 17), they asked Hargitay to be godmother.

"The birth of his first child and being privy to his amazing, solid relationship with his wife, before I had that for myself — I think that Chris and Sherman played a really big role for me, to see this really stable couple that loved each other," Hargitay says.

Courtesy ChristopherMeloni Christopher Meloni and Sherman Williams with their children

Courtesy Mariska Hargitay Mariska Hargitay and Peter Hermann with their children

Watch the full episode of People Cover Story: Mariska Hargitay and Christopher Meloni on PeopleTV.com or on the PeopleTV app.

"And it made me feel even safer with him, as opposed to: 'Great guy — but single.' Or 'Great guy — except for his romantic life.' Instead, he's this man who is as solid as a rock, and who is that rock in his relationship," she adds. "And I got to lean on it when I needed to. It was like family."

Ruven Afanador Christopher Meloni and Mariska Hargitay

When Meloni abruptly left the show in 2011 after contract negotiations fell apart, Hargitay continued playing Benson and in 2019, SVU became the longest-running drama series in TV history.

Despite his exit from the show, "we stayed connected," Meloni says.

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That connection has never been more apparent than when the two began filming again for SVU.

"It was Pavlovian: Ring that bell, and you get right into Stabler and Benson," says Meloni.

"There was so much shorthand between us, which all goes back to the trust we have," Hargitay adds. "He's always made me feel like I could just jump off the ledge, the cliff, the bridge, and he would catch me, in so many ways, whether it was comedy or acting or friendship."

"It's simple," Meloni says. "We have each other's back."