With each sequel, the Rambo franchise gets weaker and the violence and special effects get more over the top. There must be an end to this somewhere. 

Rambo is again living in Thailand when he is approached by a religious mission wanting his help by taking them into Burma by boat where they plan to pass out religious literature and administer to the sick and wounded in the rebel camps. Rambo initially refuses but is drawn in by the pleas of a woman with the group, Sarah Miller, played by Julie Benz. 

As Rambo takes the group up river they are stopped by a boat filled with local pirates. After a short, unproductive discussion, Rambo kills them all, which shocks the religious group but they plead with him to go on so he delivers them to the camps. 

After Rambo leaves, the camps are attacked and the group is taken captive.The murder and destruction of the camp is shown in very graphic detail and repeated over and over. Rambo is then recruited by the minister for the group to take in a band of Mercenaries the Church has hired to rescue the captives. Rambo agrees and starts back up river. The poor quality of the Mercenaries is reflective of the poor quality of the movie. Why would Rambo travel in such circles?

The rescue is completed followed by a chase by the Army in which Rambo and Sarah Miller along with the one seemingly trust worthy Mercenary get separated from the main group of Mercenaries. The Mercenaries are then captured and being tortured by the Army.  Rambo and friend must free them with an attack which they proceed to do aided by a heavy machine gun they are conveniently able to capture and have perfectly placed to decimate huge numbers of the Army. Again the violence is shown in extremely graphic detail with each shot bringing an explosion of blood, gore and body parts. Suddenly the second rate Mercenaries, when rescued by Rambo, become experts and the Army masses are destroyed. 

Rambo is once again successful in the rescue of the captives. Stallone, however, may have sacrificed what ever professional pride he had left