The inside joke about Jack's scab
The crew and cast spend many months working together in many production movies, such as the Pirates of the Caribbean series. They all become close and develop their little inside jokes that we never hear. There is an in-joke that made its way into a film. The make-up team and Johnny Depp had an inside joke that Captain Jack Sparrow had a bacterial infection spread through intimate contact, and that is why he has a scab on his chin that starts off with a small one in the first movie and gets more evident throughout the sequels.