"NCIS" season 13 returns to the airwaves on Feb. 9, with the airing of the "Decompressed" entitled episode.

According to Carter Matt, the episode finds the crew investigating the brutal murder of a deep sea diver killed while on the job. The grisly crime forces the victim's body and his coworkers to have to remain underwater for four days in a high-tech decompression chamber while the gang probes the mysterious circumstances.

Maya Stojan guest stars as deep-sea diver Meredith Ragen.

Meanwhile, plans for Michael Weatherly's series' departure as Agent Anthony DiNozzo continue to develop. A regular on the series for all of its 13 seasons, Weatherly recently announced he will be leaving the show at the end of the season to pursue other interests.

Several media outlets have previously reported at least part of the plan calls for the instant addition of two new series regulars for TV's most-watched drama, one of them a woman named Tess more elaborately described as "quick-witted, sarcastic, shrewd" and "two parts bulldog, one part sweet kitten."

Industry sources also indicate CBS is seeking a "name" actress for the three-time divorced character, also described as someone "in her late 30s, who has recently transferred to D.C. from New York City's Counter-Terrorism Unit."  

As for just how Weatherly's character will leave the long-running series, details remain sketchy, though word recently leaked that Scottie Thompson will be returning as Jeanne Benoit prior to his sendoff. Several media sites have also speculated former series regular Cote de Pablo (Ziva David) could also be returning for a special guest appearance.

Weatherly's exit leaves only Mark Harmon (Agent Leroy Jethro Gibbs), Pauley Perrette (Abby Sciuto) and David McCallum (Donald "Ducky" Mallard) as original characters remaining on the long-running series.

No timetable has been given for when the episodes starring Thompson might air.