The person who's been closing in on Red by killing off members of his inner circle and, on Thursday's episode, trying to poison Red himself, is apparently Dembe (Hisham Tawfiq), Red's bodyguard and all-around right-hand man.
As for the why behind Dembe's betrayal, we'll have to wait until The Blacklist returns with new episodes in April to find out, but the how became clear in the final (as well as, in retrospect, the opening) moments of Thursday's episode.
In order to root out "the traitor in the family," as he puts it, Red summons together the 11 people who had access to the bank account from which money was withdrawn and sent to Isabella Stone (Melora Hardin). Dembe warns Red that that's a dangerous move, but Red insists it's the only way.
As it turns out, Dembe is right. Red doesn't remember anything about the dinner, instead waking up in a makeshift medical facility, where he's informed he's been poisoned and only has a day or two to live. According to the doctor, Dembe is the one who brought Red to the hospital, but now he's nowhere to be found.
With the help of the task force, Red retraces his steps and discovers that the poison in question came from a serpentarium owner known as "The Apothecary," who provides deadly toxins to people who want to commit untraceable murders (and who, incidentally, has recently impregnated his wife, whom he keeps sedated and imprisoned in a bedroom).
Red initially suspects that the traitor is his accountant, Marvin Gerard, who is absent at the dinner and sends his regrets along with a bottle of wine, which Red assumes was used to poison him. But when Red interrogates Marvin — after receiving the antidote, getting some of his strength back, and obtaining Marvin's whereabouts from Jelly Bean(!!) — the terrified lawyer spins a pretty convincing yarn that he has no idea what Red's talking about, and that he missed the dinner because he and his wife were on their way to a yoga retreat.
Red doesn't believe a word of it, but luckily for Marvin, Reddington gets an emergency call from Liz (Megan Boone) informing him that the toxicology report came back and indicated that there's no way the poison could have been given to Red through the wine. It must have come through something with a much higher alcohol content... like the scotch Red and Dembe were drinking when Red came up with his plan in the first place.
The episode ends with a shot of Dembe walking the streets of New York City and ducking into a subway station. Where is he going? Surely Dembe knows better than anyone that Red has a knack for tracking down and punishing those who become disloyal to him.
But this wouldn't be the first time Dembe has betrayed Red of late. Remember, he told Liz a few episodes ago that Red had killed Mr. Kaplan (Susan Blommaert). Is this whole thing an elaborate way of Dembe getting revenge on his old friend's behalf? On the other hand, during that whole speech, Dembe seemed genuinely concerned about his boss' well-being and mental state. It's a mystery why he would want to put that to the test. And if Dembe is the one who poisoned Red, why would he bring him to the hospital? Is it possible someone's setting him up?
All questions we'll have a couple of months to ponder...
The Blacklist returns with new episodes in April.