Liz Keen is searching for the truth about her father, and the Blacklist's 'Red' Reddington is her only lead.

Which Blacklist Member Is Lucy Brooks/Jolene Associated With?

While her past may have been shrouded in mystery long before Red (James Spader) entered her life, Liz (Megan Boone) was seemingly content living with the information her adoptive father, Sam, had managed to supply her with. What she didn't know, however, was that Sam and Red has their own history, and Sam's death would leave only one person that could connect the dots between all their lives.

"She doesn't know about a portion of her life prior to being four years old," Boone explained in a Behind the Blacklist feature for "Anslo Garrick - Part 1." "The man who died, Sam, may have the answers but since he's gone now there's a lot of questions about who I am and what my life really is about."

Where Will James Spader's Red Turn For Answers About His Family On 'The Blacklist'? Will He Grow To Regret Killing A Prime Lead?

A newly released promo for The Blacklist continues to tease fans with the "father question" as the series heads into the second off of its inaugural season (see video below). While Red previously informed Liz that he is not her father, the master criminal uses the new preview to explain that their relationship cannot be easily explained.

However, Spader believes that continuing element of mystery is integral to the series.

"Particulars and specifics of that relationship, I do not know," Spader told the Today Show when asked if he knew how Liz and Red are connected.  "But, ultimately, that is a great deal of what the show is about. I think you just have to sort of allow the audience to glimpse behind the curtain and then shut it quickly in their face."

Will viewers find out who Liz's father is before season one draws to a close? Tell us what you think by taking the poll below!

The Blacklist will return to NBC with new episodes on Feb. 24.