NCIS: Los Angeles is heading into deep water with their season 5 finale.

Callen & Sam Trapped In A Sinking Submarine, Deeks & Kensi Take To The Sky In Finale/Premiere Combo? [BTS PHOTOS]

The CBS drama is closing out the year by putting the special operations team in a whole new batch of trouble, and this time they won't have Hetty (Linda Hunt) to bail them out when the mission goes sideways.

The diminutive operations manager may be small in stature, but her formidable skills and experience have pulled her Los Angeles team from the fire on multiple occasions. However, Hetty's recent decision to send Kensi (Daniela Ruah) to Afghanistan and the subsequent White Ghost debacle has put the tea connoisseur is bad standing with the higher ups. As Hetty heads to Washington for an inquiry, her team will find themselves in an increasingly difficult situation.

Densi Drama Spills Over Into 'NCIS: LA' Premiere? Who Is Kensi Bonding With?

Busy investigating a cocaine smuggling, Callen (Chris O'Donnell) and Co. will be in hot pursuit of a missing submarine and the cartel that is planning on utilizing it to transport billions of dollars worth of drugs. While Deeks (Eric Christian Olsen) and Kensi's relationship sails into rough waters when they have to partner with returning DEA Agent Talia Del Campo (Mercedes Masohn), it looks like Sam (LL Cool J) and G will be heading underwater as the season closes on a cliffhanger.

"[They are] in extreme jeopardy in a place that they've never been, and in a situation that appears almost insurmountable for them," teased series creator Shane Brennan, according to TV Guide.

Scroll through the gallery above and click the preview below to get a glimpse of what fresh danger is in store for the team during "In Too Deep."

NCIS: LA airs Tuesdays at 9 p.m. ET on CBS.