It’s even questionable whether Liz and Red will end up coming back to the FBI at this point. A lot could happen, and it’s possible that the writers might have plans to continue the formulaic nature of the show but at the same time change the formula.
It would be interesting to see both characters operating outside of their natural environment and the setting we saw them in during the previous seasons, but it could also be a good change for the show if it’s done right.
Especially if we’re shown the darker side of the show’s world, and the characters are allowed to dig deeper into the mentalities of those they’re coming up against, now that they don’t work for the FBI anymore.
But in the end, the most likely long-term development is that we’re going to see Red and Liz getting back with the FBI at some point, possibly even early on in the season, and from there on the story is going to continue in the same way it was running before. Judging by online discussions, this seems to be the version that fans would be most interested in seeing as well, so hopefully the producers and writers are listening to online feedback and are keeping the show in tune with their fans’ interests.
In Season 2, when Keen shot the A.G., she had flashbacks of a man beating a woman and she killed him. Later on, it was revealed that both man and wife were deep plant KGB moles and some terrible confession/confrontation set the man off against the wife. What was left out was there was a fire and how it started. We know Reddington was burnt in that fire and rescued the girl. My surmise is that Reddington compromised the KGB operation by impregnating the KBG wife and she bore him a daughter Keen, his illegitimate daughter and he was burned rescuing her while burning down the house.