'NCIS: LA' season 8 episode 13 spoilers: Sam goes undercover; Callen and Anna discuss their relationship

Sam (LL Cool J) goes on an undercover mission on his own when "NCIS: Los Angeles" returns for the back half of season 8 next year.

Titled "Kulinda," the series' upcoming winter premiere will see one of the team go undercover to solve a high-profile case. According to the official synopsis, a Navy reservist is killed while protecting a city councilman. To get more information about the case, Sam is sent undercover to a private security firm with connections to various criminal organizations. Also, Callen (Chris O'Donnell) and Anna (guest star Bar Paly) will try to work out the next step they will take in their relationship.

While Sam usually takes on cases with his trusted buddy, Callen, it will be interesting to see the agent work on a new case alone. Although details on how he will enter the security firm remain under wraps, it is speculated that he will pose as a new recruit in the company. As for Callen and Anna's relationship, a lot of viewers cheered when the agent started showing his romantic feelings for the gorgeous blonde specialist. However, it seems that they are still not ready to share their relationship with their friends, so they would have to talk about it first.

The show left off last week with Anna assisting the NCIS crew in their search for a missing female Navy Lieutenant Commander. The officer was last seen working for the NSA to solve cyber threats, leading the team to speculate that her disappearance was connected to her job. It turned out that the officer's journalist boyfriend came up with a list of corrupt men, and they tried to silence him by kidnapping his beloved girlfriend.

The 8th season of "NCIS: Los Angeles" returns to the small screen on Sunday, Jan. 8, at 8 p.m. ET on CBS.