Considering their mission in Mexico was off-the-books and the episode is called “To Live And Die In Mexico,” we may want to start worrying, if not panicking.
Deeks’ absence doesn’t necessarily mean that fans need to start panicking.
The episode description reveals that Callen, Sam, and Kensi will have “an unconscious Deeks in tow” as they deal with their own grave injuries and struggle to find a way to contact the team in Los Angeles.
In the first look at the aftermath of Season 10’s cliffhanger, Deeks is unconscious and not ready to run off on any escape missions without some help, but he’s on a stretcher and looks to be getting some help.