Opening Scene of the movie is a man and woman walking through a crowded office they work at when during the middle of their work conversation I guess a X coworker who was fired went postal and opened up fire with a hand gun with an extended clip and winded up killing alot of people in the office including the man and woman having the convo
the first two things that came to mind were The Rapture (1991) and The X-Files S05E19: Folie a deux. David Duchovny figures in both, so i wonder if that has something to do with it.
Possibly “I can make you love me” starring Richard Thomas who is an active shooter where he works.