Law & Order: Special Victims Unit

When Law & Order: SVU showrunner Neal Baer began developing a character that would be a master manipulator who prodigiously procreates, he wrote the role with John Stamos in mind — even though that goes against type for the veteran actor.

"We wanted someone completely charming, affable, very handsome, had a way with women, that people could really connect to," Baer said in a recent conference call. "We wanted someone who is very appealing because these guys are often very appealing guys. We wrote it with [Stamos] in mind hoping he would do it."

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In Wednesday's episode "Bang" (10/9c on NBC) Stamos plays Ken Turner, a man who's fathered more than 40 children — because he's convinced himself it's because he loves babies. Unfortunately when detectives Benson (Mariska Hargitay) and Stabler (Chris Meloni) dig more deeply into the case of this "reproductive abuse," they find the law is on Turner's side.

"It's not illegal for a man to poke holes in his condom and a woman gets pregnant, even if it's fraud," Baer points out.

Although Benson and Stabler may have trouble bringing him to justice, Stamos hints that somebody else does. "It's not illegal, so somebody takes their own stand and brings him to justice. There's quite a dramatic ending to this show -- more blood involved in that scene than I saw in ER in four years." (Watch the clip here. Spoiler alert: It may tell you a bit too much about the ending.)

One of the challenges Baer and his team of writers sometimes face is making bad guys likeable enough for viewers to be drawn in. The executive producer knew that wouldn't be a problem with Stamos, even though he's so fondly remembered as Uncle Jesse on Full House.

"We wanted to get into someone's head in a way that we could understand why he was thinking this way as opposed to 'this is an evil guy' ... If you didn't like him from the beginning then you're not taken on this journey," Baer said.

Stamos adds, "You buy into, 'Oh, it's John Stamos, he's sweet with the ladies, he's charming, ' but you find out he's really an evil, deceptive man and for very selfish reasons procreating and wanting more of his DNA in the world."

The 47-year-old actor, whose recent guest appearances include Glee, says that his SVU character is "truly the farthest thing I've done on television and movies from who I really am." And that's exactly why he went for it.

"I remember doing Cabaret and people walking out of the theater because they wanted to see Uncle Jesse. That's why roles like this scared me over the last few years and I found myself doing safe stuff. Recently, I stopped," he says. "I've been waiting for a role like this to come around."

Watch an exclusive behind-the-scenes clip with Lori Singer: