Rizzoli & Isles is making the most of its time left.

The TNT drama, which kicks off the back half of Season 6 Tuesday (9/8c) with back-to-back episodes, will end after its upcoming seventh season. Executive producer Jan Nash says the cast and crew found out about the cancellation "the same time everybody else did" — when TNT President Kevin Reilly announced it at the Television Critics Association winter previews in January. But they were prepared for it.

"We certainly had an inkling when they ordered 13 [episodes] rather than the usual 16 or 18," Nash tells TVGuide.com. "We figured that might be the way this would play out. We designed Season 7 so that it could act as a series finale or just B story lines that we pull back on at the end to have them continue on. But I think with where we left off and what we already had planned work in our favor [going into the final season]."

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Where the show left off was with yet another precarious life-or-death situation involving our heroines. An unknown baddie who's ostensibly after Jane (Angie Harmon) kidnapped Maura (Sasha Alexander) at the end of the midseason finale. Naturally, Maura will make it out alive, and her captor will be revealed — but that person is not the ultimate culprit, just merely working for him or her. Though the show has been wont to wrap up its cliff-hangers right away upon return, Nash chose to stretch this mystery out.

"One of the things we talked about was how much we enjoyed the serial killer arc that was set up in the pilot of the show," Nash says. "We wanted to come up with that same sort of energy without repeating [it]. We decided that something with a slow burn ... and built-in intensity that became a threat that encompassed Jane, and then Maura, would be fun and interesting. When we got into it, we loved it more and more, so when we got to this moment, it felt like to solve that mystery of who took Maura and have that be the end wouldn't do justice to some of the elements we created. When we laid it out, it actually does continue into the start of Season 7. It's not over yet at the end of this season."

In sketching out who would be their final big bad, Nash wanted him/her to be a formidable foe, whose identity will be revealed in the penultimate episode of Season 6, to face off against Jane and Maura. Moreover, this villain is a personal threat rather than a professional one to Jane — "someone from within the world, rather than a boogeyman from the outside" — hence Jane's loved ones are targeted. Maura was the first and definitely won't be the last.

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"We'll get more into the psychology of it," Nash says. "This is a person who has targeted Jane Rizzoli and for their own reasons, [is] trying to cause harm to Jane personally, professionally, physically, emotionally. How do you get to anyone? The way to get to them most deeply is to go after the people they care about. These are the people that Jane cares about: Maura, Angela [Lorraine Bracco], Korsak [Bruce McGrill]. When any one of them suffers, they all suffer. Jane is not acting with callous disregard for her own personal safety, but she really cares about this family of people. This is her biggest threat yet. She will do anything for them — as will they. They're all in it together, which is what makes this show so special."

The current plan is for the arc to conclude in the second episode of Season 7. "It started in Episode 7 of Season 6 and won't be finished until Episode 2 of Season 7. I don't know if we can go on any longer," Nash jokes. After that, all that's left is plotting the final 11 episodes. "We do have an idea of what we're aimed at," she says of the series finale. "The best idea wins, so if somebody has a better idea, then that's what we'll do. We have our 100th episode in the middle of the season, so we want to do a big, flashy 100th episode. There are a lot of opportunities to do fun things this year."

"Fun" is the operative word for Season 7, as the cast and crew hope to end the show on a high note for their loyal fans. "I haven't been here as long as some other people," Nash, who joined in Season 5, says. "This is a very close-knit group. I think there's a lot of gratitude for having been on such a long-running, successful show. I think we really just want to go out having a wonderful experience doing the work we love so much but also trying to make something the large and loyal audience of this show will enjoy. That has been our mantra. It's hard to say goodbye. I've been on shows that have had long runs and it's hard to come to [the] end of something, but it is certainly much more satisfying to be able to do it in a way where you can plan and feel like you got to service the characters properly."

Rizzoli & Isles airs Tuesdays at 9/8c on TNT. Watch the trailer for the new episodes below.