Mr. Kaplan (Susan Blommaert) is coming for Red (James Spader) in the upcoming episode of "The Blacklist."

Fans of the series can look forward to Mr. Kaplan's return in January, according to Game N Guide. That brief glimpse of her in the show's last episode for the year is enough to hint that she will come back strong when the new year starts.

Viewers finally learned what happened to Mr. Kaplan after Red shot her. She survived but somehow found herself trapped with an unknown man determined to keep her.

It has been previously teased that Blommaert's character still has some unfinished business to do in the show. One of the predictions is she will be planning her revenge on Red who threw her away like a rug the moment she betrayed him.

Mr. Kaplan helped Liz fake her death to get some answers to her life-long question about her identity. That time, Alexander Kirk (Ulrich Thomsen) was the only one who seemed to know the truth. When Liz's lies were discovered, Mr. Kaplan's part in the heist was also exposed.

Red could not believe she betrayed him. When she tried to make amends, he reciprocated by putting a bullet in her chest. When Mr. Kaplan returns, it is possible that she will seek retribution from the man she considered the most important in her life. Will Red once again try to kill her?

Meanwhile, the promo reveals that Red's team is hiding a mole. He and Harold (Henry Lennix) will discover the shocking truth. One of the FBI task force members is a spy working for an international terrorist and he/she must be stopped. Who among Samar (Mozhan Marnò), Liz (Megan Boone), Ressler (Diego Klattenhoff) and Aram (Amir Arison) is the culprit?

In the clip, he/she sets up an ambush that takes out some of Ressler's men. Meanwhile, Liz expresses her concern over the betrayal. In the last scene, Harold is shown talking to someone. It looks like he has found the mole.

"The Blacklist" season 4 returns on Thursday, Jan. 5, 2017 at 10 p.m. EST on NBC.