Sam and Callen are kidnapped when they follow up on a lead on NCIS: Los Angeles. "Forest For the Trees" is the 14th episode of the show's sixth season.
(Hetty approaches Callen as he is sleeping, he wakes up staring at Hetty) Hetty: Did you catch him this time? You were twitching like a sleeping dog. Callen: Well, you now what they say about sleeping dogs. (looks at Hetty)