It's time to get down to brass tacks, Blacklist fans. Who is the father?

The mystery of her paternity has fueled Liz Keen's (Megan Boone) journey from demure profiler to Red's (James Spader) right-hand (wo)man, but the arrival of Alexander Kirk (Ulrich Thomsen) has thrown all her research into disarray. Everything Red has ever disclosed indicates that Papa Keen died the night of the fire, which, unless Reddington is being metaphorical (we wouldn't put it past him), means Kirk is playing a dangerous game.

A promo for season 4 has Liz reiterating her most famous inquiry as she chats with Red - "Are you my father?"

The Blacklist will tackle that question head on during the fall premiere. Titled "Esteban," the Sept. 22 episode will pick up in the wake of Liz's kidnapping. Now that Red and the Post office team know the truth about the Keen's Cuban relocation, it remains to be seen who will join the rescue mission.

"After Liz (Megan Boone) is abducted by a man claiming to be her father, Red (James Spader) sets out to find her at any cost," NBC teased. "Meanwhile, the Task Force grapples with the shocking news that Liz is still alive."

For now, viewers should remember that, aside from Red's statements, there is no reason to believe Kirk isn't telling the truth. You know, aside from the whole kidnapping debacle.

"I don't know why we wouldn't believe him. Red's said before that he's not Liz's father. This man shows up in her life and says he's her father. Liz should take him at his word," series creator Jon Bokenkamp told Entertainment Weekly. "She thought she shot her father. It raises a number of questions, which is going to be the joy of season 4."

Catch The Blacklist season 4 premiere Sept. 22 at 10 p.m. ET on NBC.

Tags: The Blacklist television nbc