Callen's (Chris O'Donnell) life might turn upside down in the upcoming seventh season of "NCIS: LA." 

The previous season ended when Callen found out that his dead father is actually alive, and the upcoming season of the series is expected to tie up the loose ends of that arc by giving the answers that he has been looking for.  

"The very heart of what this show is about is Callen's search for his family," executive producer Shane Brennan exclusively shared with TVGuide.com. "We are stepping closer and closer to finally giving Callen closure." 

Spoilers claim that Callen and the rest of the members of NCIS will be facing someone from his past. But that person will not be a stranger, since the viewers of the show already met that character before.

Brennan also told the website that Callen's personality will turn a little darker this season.

"It puts him in a fairly difficult position with Hetty (Linda Hunt). It puts him in a very, very difficult position with Sam (LL Cool J) - and as a result, puts him in a difficult position with the rest of the team. We've never seen Sam or Hetty in this position with Callen before," the executive producer said. 

Although Callen has been off-tracked from his duty in the past, Brennan said that he and his closest friends in the team will have several interesting exchanges about being loyal and having a grasp of what is really happening around him. The information is featured in the latest promo trailer for the series. 

The intense promo also shows Hetty and Sam having a heated discussion about how they must handle the problem with their friend. One of them wants to give Callen the stern discipline that he deserves, while the other believes that they should just wait until he gets back on track. 

"NCIS: LA" returns for its seventh season on Monday, Sept. 21, on CBS.