I've mentioned many times that two people did a head-nod as they were walking out, before the Oswald shooting went down. One was Detective McMillan and the other was Captain Fritz.
A head-nod? When it was just supposed to be a guy being walked 30 feet to a car? What's to nod about?
I've had the Wizard's gif of McMillan doing it for a long time, but now he has done one of Fritz doing it as well. So, here are both of them doing it. The message was: "It's go-time."