After it was revealed in the season 3 finale that Alexander Kirk (Ulrich Thomsen) was actually Liz Keen's (Megan Boone) father Constantine Rostova, fans are wondering if he will be Red and Liz's next nemesis in the fourth season of "The Blacklist" beginning this September.

In the final episode of season 3, Kirk made a shocking revelation when he told Liz that he is her real father. But this does not mean that the mysterious businessman will spare Liz from his evil plans against Red (James Spader), who happens to be very close to her.

Speaking with Entertainment Weekly, executive producer John Eisendrath teased that Kirk will play a big role in the lives of Liz and Red in season 4.

"It's definitely an, 'Oh my God, who really is this person, what's his agenda and what is going to happen to Liz?'" Eisendrath said. "We're left with Red and everyone aware of the fact that Liz is alive, and she's also been abducted."

This means that in spite of Liz's reported connection with her abductor, Red will still think that Kirk is their biggest enemy in the upcoming season of the show.

Meanwhile, Boone revealed that Liz is still not losing her hopes about finding out about her real connection with Red in a separate interview with EW. But this time, she will use a different method to force him to spit out the truth.

"I think she may have given up on getting answers from him because it's proven futile. If she is going to find out, she has to find someone who has the answers and is willing to share them. She has to branch out," the actress said.

Liz's relationship with her husband Tom (Ryan Eggold) and their newborn daughter will also be tackled in "The Blacklist" season 4, which premieres on NBC on Sept. 22.