NCIS: Los Angeles 12x17 "Through the Looking Glass" Season 12 Episode 17 Promo Trailer HD - When a Naval Intelligence Officer is tortured and murdered, NCIS must work with Joelle (Elizabeth Boush), who informs them that other CIA operatives are being killed in the same way. Also, Kensi receives a threatening postcard from David Kessler (Frank Military), the sociopath who is obsessed with her, on NCIS: LOS ANGELES, Sunday, May 16th on CBS.