'Castle' Season 7 finale spoilers, Season 8 plot news: Series creators talk new season, Main character to be killed off?

Nathan Fillion and Stana Katic from ABC's CastleABC

Before ABC's renewals were announced this week, the creators of 'Castle' had no idea if the show would be back for season 8, so show creators Andrew Marlowe and Terri Edda Miller wrote the season 7 finale in a way that could provide closure to their characters' stories but still leave things open to the possibility that storylines could continue in case of a renewal.

The season finale, which airs on May 11, could have been the show's last episode, but Marlowe and Miller wanted their fans to be happy with whatever happens to Richard Castle (Nathan Fillion) and Kate Beckett (Stana Katic).

"We're on pins and needles like the rest of the world," said Marlowe to Us Weekly before the renewals were announced.

"But we're very happy with the end of season 7," added Miller.

Marlowe told the magazine that in the past, they were aware whether or not 'Castle' would be coming back, so they were able to structure "fun, engaging cliffhangers" that would keep the fans thinking about what's next for Castle and Beckett in the coming season.

"But this season, we knew there was a chance that the show might not return. And given that, we wanted to make sure that the fans had some sense of resolution and some sense of good feelings about the characters, so we're really satisfied with where we leave off if this is the last show," Marlowe explained.

Now that the show has been renewed, the show creators are looking at possible topics for the new season, and one possible angle that they said might be explored is more trouble coming from Senator Bracken, the man responsible for Johanna Beckett's murder.

Meanwhile, many fans are speculating that Beckett could be killed off, since Stana Katic still hasn't signed on to reprise her role for the new season, but Marlowe and Miller quickly dismissed that rumor.

"I think for us that's off the table. For us, we've been telling a love story for the last seven years," said Marlowe.

"I think that would be a huge betrayal of our fans," Miller added.

Watch the season 7 finale of 'Castle' on Monday, May 11 at 10/9c on ABC.