Cant remember a murder mystery movie.

There s a movie that I cant remember the name of or the actors in it. I can only remember a few scenes of it. I tried to look it up on the "what is my movie" website but it didnt work... so what i remember is within the first few minutes of the movie (or maybe even the first scene) a man walks out of his house, someone yells something (that is probably extremely significant but i cant remember) and then shoots the man... its kind of a murder mystery.. and it involved a terrorist group or gang or something that went by the name of night-something... and then i remember a scene where there was an old man and he went to get a carton of milk and he looked at it and realized something was wrong and that it was poisoned ... PLEASE HELP

The Final Option?

Sorry.

I almost want to say Edge of Darkness with Mel Gibson but it's his daughter that gets shot.

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The older I get, the more I understand Michael Douglas' character in "Falling Down"