A Crazy Night (1970)

Two minutes to 9pm, just before closing time two black-suit men shows up unexpectedly in a grocery to declare they came from The Office, and have to do an inventory immediately. The boss first try to bribe them, and as it does't work hide all the incriminating documents. The black-suit guys act weird all the way, try to take separate the staff who had to stay longer and expose one of them as their snitch. After a short while even a gun turn up from their case.