"The Blacklist" season 4, episode 5 might see Elizabeth Keen betray Red.

"Liz's loyalties are tested as Red takes action on an operation to intercept Alexander Kirk. Meanwhile the Task Force races to find a killer who targets inventors of revolutionary technology," reads the synopsis, via Catermatt.

The official synopsis for the episode teases that Liz may have to make some tough choices. It can be recalled that in the previous episodes, Liz found it hard to trust the people around her. Aside from the fact that Red has remained secretive, Alexander Kirk's revelation that he was her biological father left her confused. Liz could not bring herself to trust his words because he had already hid many things from her, including the rare genetic disease which, according to Kirk, forced him to look for his only child after years of being away from her.

According to reports, Liz and Red's already tattered relationship will be put to test again. Red will move forward with his plan to use Dr. Sebastian Reifler, Kir's hematologist, to track him down. However, it is possible that Liz might do something to stop him after she had learned that Red might have just been lying to her again.

The trailer for the upcoming episode shows Liz coming across a DNA report which suggests that Red might have lied about being her biological father. As a result, Liz becomes desperate to take back Agnes. It is possible that she will resort to reckless means as she tries to rescue her daughter.

"The Blacklist" season 4, episode 5 airs on Oct. 20, 10:00 p.m. on NBC.