It's time for NCIS: Los Angeles to take a closer look at Arkady Kolcheck in "Kolcheck, A."

'NCIS: LA' Season 6: Finale Puts Major Character In A 'Precarious Position', EP Teases 'Chernoff, K'

Callen's (Chris O'Donnell) former KGB pal is neck deep in a case that will define the last three episodes of season 6. Kolcheck (Vyto Ruginis) will become the eponymous member of the penultimate episode, during which the Office of Special Projects will fight to track down Arkady and his missing oil tanker.

"Callen and Sam search for answers when they find dead crew members from the missing oil tanker used in Arkady's deal with Russia, and also discover Arkady's personal connection to the ship," CBS teased in regards to episode 23.

'NCIS: LA' Season 6 Spoilers: EP Teases 'Enlightening' Finale, Air Date Set

As the team digs into Arkady's mysterious deals, Callen will be able to learn more about his past. Unfortunately, the agent's curiosity may get in the way of the case. By time the finale rolls around, it seems Callen will have to precariously balance his job against his desire to unravel the mystery of his origins.

Find out more when NCIS: LA airs Mondays at 10 p.m. ET on CBS. Click the video below to see a preview for the series' next episode, "Field of Fire."

Tags: NCIS: LA NCIS: Los Angeles television CBS