NCIS

Whenever we see flashbacks featuring young Gibbs, the younger version is played by Mark Harmon's son, Sean.

The sound heard at the beginning and end of each act, when the scene goes to black and white is Donald P. Bellisario making that noise into a microphone. He wanted a unique way of bookending each act.

A satellite image of the Santiago Bernabeu Stadium in Madrid sometimes appears on Gibbs' computer.