'The Blacklist' season 4 episode 12 spoilers: Red turns to Tom for help

For the third time in "The Blacklist" season 4, Ryan Eggold returns as Tom Keen to take part in an important mission in the upcoming episode, "Natalie Luca."

Elizabeth's (Megan Boone) baby daddy will play a crucial role once more in Red's (James Spader) latest dealing, and Tom might just be the man who can save him.

Red will be the target of a destructive attack that will give him no choice but to seek help. "It seems my operation is under siege," he says in the promo for "The Blacklist" season 4, episode 9.

He turns to Tom for help and as seen in the preview, Red personally visits him at his and Elizabeth's home. Understandably, he is surprised he is the one Red wants to see.

The synopsis for "The Blacklist" season 4, episode 9 teases that Red will get the assistance of Tom for "an undercover operation inside his criminal organization."

As this happens in the episode, the task force will be busy going after an assassin who kills his victims by infecting them with a fatal disease.

It will be quite difficult to catch up to the assassin as he was described in the synopsis for "The Blacklist" season 4, episode 9 as "elusive."

As for Tom, he will soon be off to the highly anticipated spinoff, "The Blacklist: Redemption," where he will be dealing with an elite mercenary group composed of some of the most dangerous blacklisters.

Eggold will star in "The Blacklist" spinoff with Famke Janssen, who played the role of Tom's mother, Susan "Scottie" Hargrave in the flagship show. However, Scottie does not know that bit yet.

The secret about their real connection will be revealed early in the spinoff and it will lead Scottie to feel betrayed. "There would be so much betrayal in it in the fact that he came in undercover, worked for her, didn't tell her that he was his son obviously," Janssen told Entertainment Weekly.

"So I'd imagine — we're not there [yet] — that if that comes to fruition, as much as there would be excitement she found her son, there would be some pain, hurt and confusion about why that was done the way it was done."

"The Blacklist" season 4, episode 9, "Natalie Luca," airs Thursday, Feb. 2, at 10 p.m. ET on NBC.