Movies and TV series that featured the KG-9 or one of its variants:

Sin City (2005)

In this comic book adaptation by Frank Miller (I think he also did 300), Clive Owen is working for the Mob and crosses paths with prostitutes packing TEC-9s.

SWAT (2003)

A movie based on the Seventies series, in this version we see the bad guys attack with the TEC-DC9 and go after the SWAT team that includes Samuel L. Jackson and Colin Farrell.

Bad Boys (1995) and Bad Boys 2 (2003)

Will Smith and Martin Lawrence star in this tale of two Miami police officers squaring up to the bad guys with the TEC-DC9.

Robocop (1987) and Robocop 2 (1990)

In these two films, we see a number of bad guys with this gun.

Miami Vice (1984)

A legendary series of the Eighties, it was remade as a movie starring Jamie Foxx and Colin Farrell, but in the original this model features right from the pilot episode.

The A-Team (1983)

Another of the most popular series from the Eighties which was adapted for the big screen, where the team leader, Hannibal, is seen with a TEC-9, among many other guns.