As Castle Season 8 enters its final stretch, the yet-to-be-renewed ABC drama is facing two different finales and three possible futures.

In response to our recent report that the stalwart drama was preparing an alternate ending for the season in the event of cancellation, co-showrunner Terence Paul Winter tells TVLine that for the Season 8 finale airing May 16 — titled “Crossfire,” in which a twist in Rick and Kate’s final pursuit of LokSat “puts their case, and their lives, in jeopardy” — “We have one ending, a cliffhanger that we’re excited about, because we believe in Castle and we believe that ABC will hopefully, hopefully bring us back.”

And if Castle does return for Season 9, it could look one of two ways: like the show that fans currently know, or a variation that accounts for an altered cast.

“Obviously our hope is that we come back ‘all hands on deck’ for Season 9, but everybody needs to make deals,” co-showrunner Alexi Hawley explains. With leads Nathan Fillion and Stana Katic at the end of their one-year contract extensions, “There’s stuff up in the air, so we are trying to leave it in a very dynamic way which leaves open the possibility that maybe the show won’t come back in the same form next season — although, again, we really hope that it does.”

Or, of course, you have the worst-case scenario — that Castle doesn’t come back at all, after a season that occasionally flirted with series-low ratings, yet in recent weeks has stabilized and even upticked.

In the event that ABC doesn’t order Season 9, the showrunners are prepping an alternate version of the season finale that properly ends the series as a whole.  “We have crafted a final scene that would exist only if we weren’t coming back,” Hawley confirms, “one that we don’t really want to get into—”

“—because our hope is that it never airs,” Winter adds.

Hawley traveled a similar road last year at this time, when as co-showrunner of The Following he set up a finale that ended with Kevin Bacon’s character venturing off to be a vigilante of sorts, as the Fox drama rode the renewal bubble. “But we can’t do that on Castle,” he says. “Castle‘s a different show, so it felt like to be fair to the fans, if we thought there was even a small chance we wouldn’t come back, we owed it to them to craft something” that offers closure.

Until ABC hands down its fateful decision, the showrunners have their “fingers crossed” that Castle does come back, and “with the whole team.” But when exactly do they need to know which version of the finale to submit for broadcast on May 16?

“Basically we have to deliver an episode on the Friday before we air,” Winter says, “and it’s up to ABC to tell us which one that is.”