In the film, Rambo sets out on a dangerous journey to Afghanistan in order to rescue his former commander and his longtime best friend, Col. Sam Trautman, from the hands of an extremely powerful and ruthless Soviet Army colonel who is bent on killing both Trautman and Rambo, while helping a local band of Afghan rebels fight against Soviet forces threatening to destroy their village.

The film was not well received by critics and grossed less than its predecessor, Rambo: First Blood Part II, earning $189 million worldwide.

After leaving the military behind, former U.S. Army Green Beret John Rambo has settled in a Thai Buddhist monastery, helping with construction work and competing in krabi–krabong matches in Bangkok, donating his winnings.

His old friend and ally Colonel Sam Trautman visits and explains that he is putting together a mercenary team for a CIA-sponsored mission to supply the Mujahideen and other tribes as they fight the Soviet Army in Afghanistan.

Embassy official Robert Griggs informs Rambo of Trautman's capture but refuses to approve a rescue mission for fear of drawing the U.S. into the war.

Aware that Trautman will die otherwise, Rambo receives permission to undertake a solo rescue on the condition that he will be disavowed in the event of capture or death.

Rambo flies to Peshawar, Pakistan, where he convinces arms dealer Mousa Ghani to bring him to Khost, the town closest to the Soviet base where Trautman is held captive.

Aided only by Mousa and a young boy named Hamid, Rambo attacks the base and inflicts significant damage before being forced to retreat.

He and Trautman rescue several other prisoners and hijack a helicopter to escape the base, but it is damaged during takeoff and crashes, forcing the escapees to flee on foot.

Suddenly, Masoud's Mujahideen forces, including Mousa and Hamid, arrive to rescue them in a massive cavalry charge.

"[6] Bullitt and Red Heat scribe Harry Kleiner was hired to write a draft, but his script was rejected by Stallone.

It was MacDonald's first film as director but he was very experienced and had directed the second unit action sequences in Rambo: First Blood Part II.

MacDonald later said, "I tried very hard to change the Rambo character a bit and make him a vulnerable and humorous person, I failed totally.

[9] The character Masoud, played by Greek actor Spiros Focás, was named after Mujahideen commander Ahmad Shah Massoud who fought the Soviets and later the Taliban.

[15][16][17][18] An extensive film score was written by Oscar-winning American composer Jerry Goldsmith, conducting the Hungarian State Opera Orchestra; however, much of it was not used.

The original album, released by Scotti Bros., contained only a portion of the new music as well as three songs, only one of which was used in the film (Bill Medley's version of "He Ain't Heavy, He's My Brother", played over the end credits).

The site's critical consensus reads: "Rambo III finds its justice-dispensing hero far from the thoughtful drama that marked the franchise's beginning -- and just as far from quality action thriller entertainment.

"[26] Metacritic gives the film a weighted average score of 36 out of 100 based on 15 critics, indicating "generally unfavorable reviews".

[28] On At the Movies, prominent critics Gene Siskel and Roger Ebert agreed that Rambo III delivers all the mechanical elements that audiences expect from a big budget action movie but lacks the heart seen in similar films such as the James Bond series and even its immediate predecessor, Rambo: First Blood Part II.