Cold open noun phrase
In a motion picture, television program or video game, a scene shown before the theme song or opening titles are shown.
The cold opening of this movie was so suspenseful that it won my attention and kept me from channel surfing.
A perfect cold opening for drama series is the one succeeding at increasing suspense.
The origin of this phrase is not clear.
A legal matter that is very easy to solve
The house owners didn't lock the doors before going out, and that's why they got broken in. This is an open and shut case.