Jane Curtin Jane Curtin

You can hear a pin drop in the Queens homicide squad as Det. Carrie Wells calls a cellphone that could belong to a serial killer she's tracking. When a drug dealer answers, she hangs up, disappointed. A familiar face in the corner makes a wisecrack and the Unforgettable cast hold back their laughs. Live from New York... it's Jane Curtin!

The Saturday Night Live alum's addition to Unforgettable is part of a mid-season tweak for the CBS procedural, which stars Poppy Montgomery as Wells, a driven cop with the extraordinary ability to remember everything she experiences. Despite consistently besting time-slot competitors Body of Proof and Parenthood in overall ratings and demos, the crime show is no sure thing for renewal.

To up its chances, cocreators Ed Redlich and John Bellucci have grown the show's family of characters. Asked by CBS to consider adding a mature actress to the cast, "right from the beginning, we thought about Jane," says Redlich. "It turned out to be a great fit." They also brought in newcomer Britt Lower to play brainy tech expert Tanya Sitkowsky. "We liked the idea of bracketing Carrie with two other very smart women," says Bellucci. "Poppy plays beautifully off both of them."

Other than a long-ago unaired pilot, this is Curtin's first role in a crime drama. "I like it a lot," says the actress, whose last major TV series was 3rd Rock From the Sun. "We have fun!" Curtin plays Dr. Joanne Webster, a formerly powerful Manhattan medical examiner demoted to Queens for insubordination. "That's fine with Webster, because it gives her more time to teach her romantic poetry class," says Curtin. "The producers wanted to bring a little levity to the group, so she's quite flippant."

Curtin's sunny presence has the cast smiling. "I'm just obsessed with Jane," says Montgomery. "I was terrified that she was coming on the show, but the moment I met her, I fell in love." Carrie and Webster "quickly bond," Montgomery reveals, especially when the doc volunteers to help Carrie investigate her sister's unsolved murder — the one case in which she can't recall the most important details.

Tonight's episode amps up the adrenaline with the introduction of a serial killer determined to get under Carrie's skin. "We always wanted to bring Carrie's investigation of her sister's murder more into the present with a serial killer who knows about her," says Redlich. "We feel it's important to give Carrie the kind of opponent that Sherlock Holmes had with Moriarty. Someone as brilliant as this guy will find Carrie's mind irresistible."

Or, at the very least, unforgettable.

Unforgettable airs Tuesdays at 10/9c on CBS.

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