Col. Carl Brewster enters the local Vietnamese town to make the ""boom-boom"" parlor off-limits because of men catching the clap. Goldman and McKay attended the funeral for Alex who was killed in the bomb explosion. Anderson and the squad have been transferred to MACV-SOG, under the command of Col. Brewster. Brewster lets Hockenberry ""volunteer"" for a special assignment ,cleaning up the whore houses. Goldman has trouble dealing with his feelings about Alex's death. Anderson is thinking about using some of his leave to go visit his daughter, but he is concerned about Goldman. Goldman returns to the unit, both he and Anderson meets up with Brewster for the first time. Goldman breaks up a party when the unit meets up with Baker again -- by telling Johnson that he is in charge of the squad while Anderson goes home for some leave. Zeke visits his ex-wife, Carol, and their daughter, Katie. Johnson finds he has a hard time filling Zeke's shoes and dealing with Percell who is on a dangerous downward spiral.

While Zeke is back in the States, Brewster sends the men out to locate a missing SOG team. Once in the bush, Team Viking locates the missing soldiers, who all appear to be dead. It is an NVA trap; the enemy opens up just as the American reach the bodies but retreat quickly when Johnson leads a counter-strike against them. Johnson faces a crisis of confidence because men under his command were killed. Ruiz is struggling with Doc Hock's pacifist attitudes, Johnson is getting worse and Taylor is losing faith in everyone. Anderson arrives back in Texas and spends time with Dr. Seymour. They spend the weekend together and discuss the days ahead, Zeke has trouble seeing any future that involves him returning to the World.

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.

McKay has a date with a ""killer"" blonde but on the way to take her shopping he ends up hitting a child with his jeep and comes in contact, for the first time, with a makeshift orphanage where he decides to get involved with the orphans. Doc finds Purcell high on grass and drugs. Purcell leave in a huff, seeking more drugs, and ends up arrested and assigned to a ""shit burner"" detail. Goldman goes to Brewster to report the massacre. Later, Goldman and Anderson are briefed on a mission into Cambodia to kidnap a defecting NVA officer. Percell tries to desert.

Taylor, Ruiz and Johnson go in search of Purcell after he goes AWOL. They look for 3 days, finally being taken to a heroin parlor by three drug dealers. Danny refuses to leave and the 3 thugs won't let the soldiers force Danny out. Later, Anderson and Team Viking are trying to find a road that is part of the Ho Chi Minh trail. When they find the road they return to the base where everyone knows about Danny. Brewster tells Goldman to solve the problem and Goldman insists upon talking about the massacre. Brewster puts his own career in jeopardy as he tries to get the army to deal with Phu An massacre. Anderson (under pressure from Goldman) organizes a commando raid and goes into Cholon to spring Purcell -- who then is forced to go through cold-turkey withdrawal. Brewster is ordered to shut up about the Phu An massacre.

The men of Team Viking are receiving medals in a ceremony in recognition of their heroism. In the midst of the ceremony, General Higgins arrives and reads out Brewster. Higgins thinks Brewster should have kept his mouth closed about Phu An. Higgins leaves with the threat that he will destroy Brewster if the colonel keeps ""forcing the issue"". Anderson talks with Percell who is off drugs, finally, and is now spending time at the Psych Ward. Doc calls home and finds out that his girl friend is sleeping with someone else. Brewster takes the story of Phu An to the press and is relieved of duty.

Out in the field, Percell captures a VC. Doc and another soldier stand guard. A second VC attacks Danny and while Doc and the other soldier watch, the first VC grabs a gun. Doc refuses to fire, despite the fact that he has the only other weapon and the third American is killed. Colonel Brewster returns for the Phu An board of inquiry. Everyone ostracizes Doc, feeling that they can't trust him. Goldman meets up with Brewster after Pop has punched the colonel out. Meanwhile, Ruiz and taylor have crawled out of the jungle after 22 days. Doc -- told he is going to be transferred out as he is ""no longer dependable"" -- meets up with Pop and goes on a bender. Ruiz leans that Suzanne has suffered a breakdown due to the stress of the job and losing him (she thought).

Anderson & Pop are having a good time at a local bar when a young trooper turns up and gets insulting to Pop -- it turns out to be Robby (Pop's son). The Phu An Board of Inquiry starts. As the situation develops and Beller realizes what his men did -- he had blocked it out -- he kills himself. Zeke and Team Viking go out with Robby on another SOG mission. They end up getting sprayed with Agent Blue. Before the end of the day, Robby ends up killed, leaving Pop to bring his son home in a body bag.

The monsoon seasons starts. Pop goes back to the States for his son's funeral, only to be blamed for the death of his son (by his wife). Goldman is upset over Beller's suicide -- feeling that the ex-friend was only another type of victim of the war. Brewster enlists Goldman for a volunteer mission to rescue MIA/POWs. AN ex-POW (very fragile) comes back to Vietnam to help plan the mission. Doc is still on base but no one will speak to him. Doc goes to talk to Goldman, begging to be part of the rescue mission but gets refused. The mission turns out to be a nightmare. The POWs were moved before the Team got there, Griner is blinded, Pop and McKay are hurt and get shipped to a hospital in Japan, Brewster is hospitalized at China Beach.