It's Office Of Special Projects Vs. Russian Mob On NCIS: Los Angeles

Actor Vyto Ruginis returns as Arkady Kolcheck in the new episode, "Mountebank."

When a prominent investment banker with ties to a Russian oligarch is murdered, Sam ( LL COOL J) must go undercover as a day trader to get to the bottom of the new case, in the NCIS: Los Angeles episode "Mountebank"—which airs Sunday, Oct. 29 at 9/8c on CBS and CBS All Access.

WATCH: Preview "Mountebank", An All-New Episode Of NCIS: Los Angeles

And who better to help out the team on a Russian mafia investigation than Anna's father, Arkady Kolcheck (guest star Vyto Ruginis)?

Meanwhile, one of Callen's ( Chris O'Donnell) aliases becomes the victim of credit card theft, and Mosely ( Nia Long) thinks it's tied to something bigger.

Will the Office of Special Projects be able to thwart the Russian mob?

STREAM: Full Episodes Of NCIS: Los Angeles On CBS All Access

Watch all-new episodes of NCIS: Los Angeles on Sundays at 9/8c on CBS and CBS All Access.