Fans of "NCIS: Los Angeles" had to forego their favorite show last week due to some scheduling changes.  This was a big disappointment after the "NCIS" crossover that fans were treated to in episode five. But the series appears to be making up for it with another action-packed episode that delves into Sam's past as the team looks for his previous partner.

In episode five of "NCIS: Los Angeles" season seven, "NCIS" special agent Anthony DiNozzo (Michael Weatherley) asks for Hetty (Linda Hunt) and the rest of the team's help when the suspect he's supposed to be escorting, Rio Syamsundin, disappears. The LA team agrees to help him look for the suspect and to keep the development a secret from Gibbs (Mark Harmon), which any "NCIS" fan knows is not a good thing to do. The crossover was fast-paced and amusing, with some enjoyable moments between Kensi (Daniela Ruah) and her crush, DiNozzo.

However, the show took a short break after that episode due to the premiere episode of "Supergirl" and the 90-minute "Scorpion" episode. But now the series is ready to come back and make the wait worthwhile with the next episode, "Unspoken."

According to a synopsis posted on the "Carter Matt" site, "NCIS: Los Angeles'" episode six sees the LA team hunting down Mark Ruiz (Anthony Ruivivar), Sam's (LL Cool J) former partner. The undercover agent disappeared shortly after purchasing some military grade explosives.

His disappearance after getting his hands on the explosives has led Callen's (Chris O'Donnell) team thinking that perhaps Ruiz' time undercover has changed him and turned him dirty. Deeks (Eric Christian Olsen) certainly thinks so, stating that people change when going on undercover assignments. However, Sam doesn't believe that his ex-partner is dirty or capable of murder.

But it would appear that Sam might have a difficult time proving that, as a teaser clip for the episode shows Ruiz apparently setting a bomb off and walking away with a suitcase (presumably filled with money).

The clip also shows that despite Sam's steadfast belief in Ruiz, there's an underlying tension between the two that has to be resolved.

Fans would learn more about the cause of this tension when "NCIS: Los Angeles" airs episode six on Nov. 2 on CBS.