With "NCIS: Los Angeles" season six to premiere its first episode this Monday, Sept. 29, fans are looking forward to the new season picking up from where it left off in season five. Its finale, "Deep Trouble," aired in May and left the audience hanging with NCIS Special Agents G. Callen (Chris O' Donnell) and Sam Hanna (LL Cool J) trapped inside a submarine.

"Deep Trouble - Part II," the first episode of "NCIS: LA" season 6 has been described as the following:

"Callen and Sam are trapped in an armed submarine that terrorists have aimed to hit an aircraft carrier in San Diego. Meanwhile, Hetty defies orders and forgoes her trip to Washington, as the team tries to locate and save Callen and Sam and prevent the terrorist attack."

As such, the group of terrorists who took Callen and Sam as their hostages is expected to set an attack on an aircraft carrier in California in the premiere episode of "NCIS: LA."

Hetty Lange (Linda Hunt) is said to cancel her trip to Washington where she is to be questioned about the "White Ghost" operation. Meanwhile, other NCIS agents including Kensi Blye (Daniela Ruah) and Nell Jones (Renee Felice Smith) are expected to address two crucial priorities – to rescue fellow agents Callen and Sam, and to stop the terrorist attack on the incoming airplane.

When it comes to Kensi and Deeks (Eric Olsen), the couple may experience some trouble, especially with Talia being around to mess up their relationship. According to the show's executive producer Shane Brennan, Talia may bring about a fight with Kensi over Deeks.

"We love this character," Brennan told TV Guide. "Without a doubt we'll be bringing her back."

He also added, "Let's just say things become heated between [Talia] and Kensi when Talia gives her some unasked-for advice. Her impact is both emotional and physical."