'Gotham': Characters everyone expects to survive ... will die

LOS ANGELES – When "Gotham" returns on Monday, April 13 with the first of the four final episodes of Season 1, Fish Mooney (Jada Pinkett Smith) is still trapped on an island with the demented Dr. Dulmacher (Colm Feore), James Gordon (Ben McKenzie) begins the investigation into a serial killer -- the Ogre (Milo Ventimiglia) -- that will impact him in a personal way and have repercussions through Season 2, and Edward Nygma (Cory Michael Smith) will continue to grow unhinged as a result of a personal crisis.

"The Penguin story will also come to a really bloody and dark conclusion in the finale as we see all his plans and machinations finally erupt and start to rip Gotham apart, and we see Gordon butting heads with the establishment inside the GCPD, which is also coming apart," executive producer John Stephens revealed in the WonderCon press room for FOX's series based on the DC Comics Super-Villains.

Despite the announcement by Jada Pinkett Smith that she is not returning for a second season of "Gotham," Stephens hedges his bets on that outcome, saying viewers will have to watch the finale and see what happens.

"I live in a world in which characters can come back frequently," Stephens tells FOX411. "DC has been really flexible about characters who we in the canon know, 'They survive, because they have to do X later.' Those characters, as we'll see going forward, even in this season, they are not invulnerable. Some of those characters who everyone will expect to survive will not survive, which will make things exciting because all the characters have a target on their back."

One thing Stephens did reveal is that Fish definitely will not die on the island. She will escape and make her way back to Gotham in time for the finale.

"We will see her with all the other characters by the end of the season, and obviously Penguin’s final rise couldn't happen without Fish being a part of it," Stephens says. "So we'll see the two of them come back together in a really, hopefully, satisfying way. "

In wrapping up the season, other characters, like Selina Kyle (Camren Bicondova) and Bruce Wayne (David Mazouz), will also take big jumps forward on the path to fulfilling the destiny we know them to have in the future. And Lucius Fox (Chris Chalk) will be introduced for a brief appearance before the finale.

"He's going to play a much larger role next season," Stephens says. "As we've seen with Bruce, he will be investigating what's going on at his family's company, and that mystery will deepen next year. Lucius starts to play a role. Bruce doesn't know who he is yet, doesn't know what his intentions really are, as they find their way towards a relationship next year, and he helps him uncover the mystery."

So what about the good guys? In the last episode that aired, Gordon started down the slippery slope of the ends justifying the means by blackmailing Commissioner Loeb (Peter Scolari) by threatening to expose the fact that his daughter killed her mother.

"He's getting dangerously close to that," McKenzie told FOX411. "I wouldn’t say he's there yet. I would say the ends justify the means is probably the final journey of Jim, in what we hope is a nice long run here, but that's the end point of the journey, I should say. The journey is each step down the spiral staircase into each circle of hell."

"Gotham" returns with new episodes on Monday, April 13 on FOX.