CSI: NY had a unique set of challenges heading into its seventh season. The show was moving to Friday nights, where the writers would have to figure out how to resolve last season's "shot in the dark" cliff-hanger involving serial killer Shane Casey (guest star Edward Furlong) and married CSIs Danny (Carmine Giovinazzo) and Lindsay (Anna Belknap) Messer.

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Then series star Melina Kanakaredes, who played Detective Stella Bonasera since the show premiered, quit just weeks before production began. "We had written six scripts over the break," executive producer Pam Veasey

tells TVGuide.com. "We developed stories that were ready to prep for shooting, and all of them involved Stella. Then, the fallout happened." Veasey says after three days of intense phone calls, she found the cloud's silver lining: Emmy and Golden Globe winner Sela Ward signed on to replace Kanakaredes on the show."Timing is everything," Ward says during a break from shooting her first episode. "I hadn't worked for a while because I was spending time with my kids. But now that they're a little bit older, I was beginning to feel a little antsy, and then I got the phone call. The thing that was attractive to me was that it was an ensemble show. I wasn't going to be carrying it all on my shoulders."

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But Veasey was still back to Square 1. "You definitely want more time to develop a character, but Sela has helped to bring so much to it in the first episode," she says. "But it did revive us a little bit. It's fun to create a new character that stays with us week after week."Ward plays Jo Danville, an amicably divorced single mom and former FBI agent from Virginia. She takes a job under Mac Taylor (Gary Sinise) at the New York crime lab to be closer to her son, who's just started college in the city. Veasey says Jo is somewhat of a fish out of water. "She's a little gentler, slower. The South doesn't move as fast as New York City, and we're not trying to change her," Veasey says. "She's a little messy. She thinks about the people first. She understands the science, but she's also a very clever assumption-maker."Sinise says he looks forward to seeing Mac and Jo build a working relationship. "Mac and Stella had a great partnership; that was established even before the first season," he says. "Now we're going to have some fun watching these characters get to know each other.

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"Jo's bringing a new approach to the work," he continues. "She's coming from the FBI and she has worked on a lot of psychological cases. It's fun to see what they're doing with her character in terms of the kind of mind games she plays, not only with the perpetrators that she goes to interrogate, but with her own peers."But what about that cliff-hanger? And where did Stella go? The resolution of the first helps explain the second, as Stella writes a letter to a distressed Lindsay that puts all the pieces together regarding Stella's absence. But much of the first episode does focus on Lindsay in the aftermath of the trauma."We spend the first act seeing where Lindsay is in her life," Veasey says. "We wanted to launch with a fun, new direction. It's five months later, but we see what she's dealt with and then happily move forward from that."

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Veasey says introducing Jo to the team will actually be helpful in the show's move to Fridays. "Once you get to add a new character, the fun of that is to let that person learn who our people are," she says. "That reintroduces them to audiences or those people who may not have watched the show."And each of the characters will get a showcase episode very early on, Veasey says. Mac will go toe-to-toe with guest stars Edward James Olmos and John Larroquette in separate stories. Adam (A.J. Buckley) will get out of the lab. Viewers will meet a partner from Danny's past. And Hawkes (Hill Harper) will be featured in an episode about a haunting in Central Park."We really landed on our characters having some personal pull in the crime story this season," Veasey says. "Whether they know the person or not, the character leads us through it rather than the events of the crime."CSI:NY premieres Friday at 9/8c on CBS.