Mariska Hargitay, Dean Winters Mariska Hargitay, Dean Winters

[WARNING: The following story reveals major details about Wednesday's episode of Law & Order: SVU. Read at your own risk.]

After weeks of teases and debate, Wednesday's Law & Order: Special Victims Unit finally revealed Detective Olivia Benson's mystery man.

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And he is... Brian Cassidy! Sure, the show had planted the seeds of the relationship in the season premiere when Benson (Mariska Hargitay) and Cassidy (Dean Winters), who hooked up way back on SVU's first season, shared a kiss in the hospital. But when TVGuide.com visited the show's New York set for the filming of the big reveal, executive producer Warren Leight confessed that when the arc was first conceived, Cassidy wasn't the writers' first choice.

"We had initially assumed it would be Haden [Harry Connick Jr.]," Leight says. "But there was something interesting between Dean and Mariska. When there was the hospital kiss scene, we were leaning towards it. But we weren't sure how much we were going to pay it off, and then we just decided to go a little farther. I think if we did our job right, everybody looking back will go, 'Duh.' But it's interesting that there's been debate."

Although the identity of Benson's secret lover might not have been completely surprising, the reveal itself was pretty spectacular. On Wednesday's episode, a woman accused Cassidy of rape when he was working undercover. When Amaro (Danny Pino) and Munch (Richard Belzer) head to Cassidy's apartment to question him, they catch Benson walking out of Cassidy's bedroom — wearing the checkered shirt last seen by Benson's companion on her flight to the Bahamas.

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Leight says he'd like to check in on Benson and Cassidy before the end of the season, but acknowledges that the show also has to deal with the episode's other big shocker. While testifying in Cassidy's trial, Amaro is forced to admit that he once carried on a long-term relationship with the sister of the drug kingpin he was targeting while working undercover. Even worse, Amaro learns that he fathered a child with the woman that he never knew about.

"Amaro is very buttoned-down. He keeps things in control, and I thought, 'I'd like to, in some way, dirty him up or knock him for a loop,'" Leight says. "There aren't tremendous legal implications for Amaro, but there are tremendous emotional implications for him. How do you tell the wife with whom you are trying to figure out your status [about this]? And when does his daughter meet her half brother?"

Adds Pino: "Amaro came in kind of as a rogue. He's tried to conform to being this detective with a suit and a tie, but he's not that guy. He's been trying to be as close to a perfect SVU detective as possible, but that mask is now off and he's been revealed. To see him as fallible and see him as imperfect is a lifeline. I like to see Amaro struggle, but he's going to do the right thing. Taking responsibility is important. ... Amaro knows his biggest responsibility is to his kids."

And how will this pair of reveals affect the partnership between Benson and Amaro? Although Pino admits his character felt betrayed by Benson's secrecy, he doesn't predict any irreparable damage. "Any relationship that is solid is forged with controversy and conflict," he says. "I think we understand each other, we trust each other and we have the ability to hurt each other. Amaro is hurt by her in the episode, but are they past the point of not being able to reconcile? Absolutely not. Partners take a hit and learn from it and hopefully it makes the relationship stronger."

What did you think of the episode's many reveals? SVU airs Wednesdays at 9/8c on NBC.