The team will be in Thanksgiving spirit in the next episode of "NCIS: Los Angeles" season 8, "Glasnost," but Callen (Chris O'Donnell) will not be feeling too festive.

While the others discuss their plans for the holiday with their families and each other, Callen will spend the day with his father but not in the way fans expect.

"NCIS: LA" season 8 episode 9 will not see the two as father and son but Callen as a police officer and Garrison (Daniel J. Travanti) a suspect of a crime.

Callen will be the one to interrogate his father, who was found in the hospital room of an NCIS patient during a radiation poisoning case. It looks like the answers he will give him will change the agent's life forever.

Garrison's involvement in the crime is to be investigated, and it looks like Callen is preparing for the worst. After all, his father could be a criminal, who even exchanged shots with Deeks (Eric Christian Olsen) in the "NCIS: LA" season 8 episode 9 promo. The clip also teases that Garrison has been harboring a "dark secret" that will be brought to light.

However, it appears that like his father, Callen has also been keeping something with Hetty (Linda Hunt) encouraging him in the promo to finish what he started.

From the looks of it, Callen will finally get to learn more about his blurry past. "I have questions, Sam. I've had them for a long time," he tells his partner (LL Cool J) with Hetty assuring him he will get them.

When Callen first met his father last season, he promised to tell him everything there is to know about his past, and it looks like this will happen in the next episode.

However, this will not change anything between the two. "You deserve to know why I wasn't part of your life ... I don't expect you to forgive me," Garrison tells his son, with Callen cutting him off saying: "I don't forgive you and I don't know that I ever will.

"NCIS: LA" season 8 episode 9, "Glasnost," is scheduled to air on Sunday, Nov. 20 at 8:30 p.m. ET on CBS.