Someone planted two kilos of heroin in the Marine compound called Camp Apache. When they are found, the Marine lieutenant and NCOs are charged with drug smuggling. They're innocent, of course, but have to prove it - a very difficult thing when they're slated to be the example that discourages other Marines from dealing in drugs! While doing that, they and their Marines and Popular Forces still have to protect Bun Hou village from the Viet Cong who keep coming through - and they have to deal with Captain Phang, the corrupt assistant district chief. Junior men are given greater responsibilities when their leaders are away defending themselves against the drug charges, and acquit themselves as well as can be expected of Marines dedicated to what they are doing. This is the most difficult mission the Marines and Popular Forces of Combined Action Platoon Tango Niner have had.