Tour of Duty (1987) : 3x5

Utter havoc reigns in the jungle after a newby makes a mistake and two other soldiers are killed going to his resuce. The men are led by Lt. Beller, and his unit has seen far too much action and too much death. Beller is an old friend of Goldman's, together they are sent back out to search for an NVA regiment. Beller tells command that his men need rest or they are going to snap but Brewster insists they must go out. Meanwhile everyone is happy to see Anderson return, except for the ever-depressed Percell. Goldman spends some time with Beller. Percell is going over the edge fast and no one knows that he has started to use drugs. Anderson discovers that Brewster is married to a Vietnamese girl and they have a child. The next day, on their mission, Percell (drugged up) starts to panic. Beller's unit creates a My Lai-type of massacre in the field and that sends Percell off the deep end and straight into the waiting arms of heroin dealers.