Gary Sinise

Does a photo from the past hold the clue to solving the CSI: NY team's latest case?

The CBS drama returns Friday (9/8c, CBS) with Mac (Gary Sinise) & Co. investigating the death of one of their own when a lab tech is found murdered in front of a New York City brownstone. But the crime scene is staged exactly like that of a famous 50-year-old cold case which Mac has seen photos of in the past.

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Executive producer Pam Veasey tells that she was inspired by a classic Weegee photo and other famous unsolved murder cases, such as the Black Dahlia, when crafting the episode, which flashes back and forth between present day and the 1950s.

"I wanted some pictures that evoked a past time," Veasey says. "I just had a fascination with the unsolved crime that's still out there and the detectives who are thinking, 'I just didn't get that one done.' Plus, I wanted a lot of old cars and really cool clothing."

The episode comes on the heels of Castle's recent 1940s noir episode and in the same season as 1960s-set shows The Playboy Club and Pan Am. But Veasey isn't worried about comparisons. "It's not like it hasn't been done before and it's not like it won't be done again," she says. "I think people are attracted to the genre of the past because shows like Mad Men were executed so well. We like to capture the past because it has mystery and glamour."

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While Mac eventually gets an assist from the detective who never solved the original murder (guest-star Lee Majors), the episode takes an emotional look at the characters who help Mac and his team behind the scenes. "When people watch our show, they think the only team investigating a crime are the stars of our show," Veasey says. "But who are those people after hours, the late shift? They're a part of our family, so that's part of the story we wanted to tell. ... A lot of techs look up to [Mac] and know so much more about him than he knows about them. We wanted to give a little life to that group of people."

Mac will also be turning his focus to his new love interest Christine (Megan Dodds), beginning with a major lip-lock in Friday's episode. "It's clear these characters both make a choice to pursue this relationship, and Mac has to come to terms with that," Veasey says. "They're letting their emotions lead them rather than their logic, and that's rare for Mac Taylor. You see him make a few different choices and easily let Christine join his family that he cares so much about. We're looking to see where we're going for that in Season 9."

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That all depends on whether CBS renews the show. For the second season in a row, Veasey and her writers had to craft a finale that could double as a series finale if the cards don't fall their way in May.

"Family has been so important on our show, so we decided if this was the series finale, we wanted to express the value of each of these characters," Veasey says. "And I think for the first time, the audience will understand how different each of them were and how essential each of them were. We've got our fingers crossed for Season 9, but we're very much a bubble show. We beat the odds last year, and now we have to compete again."

CSI: NY airs Fridays at 9/8c on CBS.