In the next episode of "NCIS: Los Angeles," Sam Hanna (LL Cool J) and G. Callen (Chris O'Donnell) track down a highly skilled assailant determined to avenge her father's death.

The sneak peeks and promotional photos for the upcoming installment titled "Forasteira" were released recently, and they showed Callen and Hanna tracking down a highly trained killer. Their investigation leads them to a bar which was burned down by the suspect. They inspect the charred premises and notice the burnt bodies.

"Someone was waiting around for these guys," Hanna says to his partner. It appears that the killer wanted to get rid of the people there. "She went through a lot of trouble to torch the place," Callen expresses as he goes through the burnt evidence. Hanna also tries to make sense of the crime scene.

Apparently, the killer wants to get revenge for the murder of her father. She thinks that she can do this by killing a Brazilian diplomat who she suspects is the mastermind of her dad's death.

Meanwhile, back at headquarters, tech specialist Eric Beale (Barrett Foa) laments to Kensi Blye (Daniela Ruah) and Nell Jones (Renee Felice Smith) that the killer is too crafty to catch on camera. However, Blye tells him to keep at it and not to give up looking for the perpetrator. Beale feels a renewed sense of encouragement.

In the last episode, Hanna and Callen had a hard time believing CIA Agent Joelle Taylor (Elizabeth Bogush) and did not want to help with her case. However, her kids were involved so they relented and agreed to assist in the investigation. In the end, they were able to capture the culprits and bring them to justice.

"NCIS: Los Angeles" season 9 episode 10 will hit the airwaves on Sunday, Dec. 10, at 9 p.m. EST on CBS.