Who is Red Reddington?

That’s the question posed by NBC in the promotion for its upcoming drama The Blacklist. Comic-Con International attendees were given a peek into the mysteries surrounding Red Reddington during a packed pilot screening and panel discussion with the creators and cast.

James Spader stars as Raymond “Red” Reddington, the world's most wanted criminal, who turns himself in to federal authorities and offers to give up “The Blacklist,” a global directory of all the criminals with whom he has worked. However, he does so only on the condition that he deal with one person: FBI Special Agent Elizabeth Keen (Megan Boone), who’s on her first day on the job. What the relationship is between Reddington and Keen and the reasons why he will only work with her aren’t known.

Following the screening, Spader and Boone were joined onstage by fellow actor Diego Klattenhoff and executive producers Jon Bokenkamp, Jon Eisendrath and John Fox for a discussion moderated by Hitfix's Alan Sepinwall.

Bokenkamp said the idea for The Blacklist originated with Fox shortly after the real-life capture of organized crime figure Whitey Bulger. “Fox had the notion of, ‘What if a person who was a lifetime criminal ... started talking?” Bokenkamp explained.

Fox chimed in, saying, “I thought if Whitey Bulger talked to the feds, which he eventually did, he would be like the Rosetta Stone of crimes. He would unlock everything — crimes he committed, crimes his friends committed, past crimes, future crimes -- so from there Jon and I started thinking about how to take this character and place him at the center of a modern show.”

He said they began fleshing out the mythology and the character, who took on a Keyser Soze-like feel of mystery and elusiveness, “with a guy who has the reputation for being the concierge of crime.”

Bokenkamp said the one element the original concept was missing was a sense of humor, which Spader brought to The Blacklist. “The delight that Red takes in being Red … it's now not so dark and straightforward,” Bokenkamp said. “That's something he brought to the show, in spades -- pun not intended.”

Spader said he wanted to be involved in the drama because he thinks Red is a great, noting that his television experience has taught him that, “You better make a choice to play a character that's going to sustain and that you're going to be curious about over a long span of time and that questions are going to go unanswered for a while — not only for the audience, but for me as well. This character seemed like that. This character seemed like such a strange mix of being dangerous and scary at times but was also compelling and part of that is because of the sense of humor.”

He also liked that, after watching the pilot, “the audience has seen a lot about the characters but at the end of the story ... you know nothing, and what you think you know, may not be so. That's great because when you're shooting your 18th episode of the season, the one thing you're looking for is a surprise. I think this show had all those possibilities.”

Sepinwall asked Spader how much he knows about the relationship between Reddington and Keen.

“I know some,” the actor replied, adding that a lot of the answers depend on the life of the series. He said that all series evolve over time, and he likes changing with the project, and having it change him. “I don't want to know everything,” Spader said. “I want to know enough to be able to do my job and nothing more.”

The executive producers were asked if Keen was Red's daughter.

“To the extent that we are going to answer that, the answer is we will explore the reasons why he has some sick and potentially twisted paternal feelings towards her,” Eidendrath replied.

“Just watch the damn show,” Spader interjected, eliciting laughter from the audience.

Bokenkamp concluded the panel by summarizing the show’s concept: “The series and the concept is very much about identity and secrets. We're going to answer some big questions that I obviously don't want to answer now. It's very much about identity and who these people are, and how none of them are exactly who they present themselves to be in the pilot. We're going to dive into that and answer a lot of those questions.”

The Blacklist premieres Monday, Sept. 23 at 10 p.m. ET/PT on NBC.