As the film opens, RAMBO, smartly dressed in a tweed sport coat, is lecturing at a university. From the context of his lecture, he seems to be simultaneously teaching calculus, archaeology and women's studies.
Suddenly, THE GENERAL appears in the doorway, clearing his throat to get RAMBO's attention.
"Excuse me class," RAMBO says.
Cut to RAMBO and THE GENERAL walking across the quad.
"Rambo, our worst fears have come to fruition. The moment you and I most dreaded," he says.
"You don't mean?"
"Yes," THE GENERAL replies. "Steam powered robots from the past have kidnapped Abraham Lincoln, and if we don't go back in time to stop them, neither of us will ever be born."
"I'm sorry General," RAMBO says, catching a Frisbee which suddenly flies into frame and hurling it offscreen, resulting in a massive explosion. "I don't do that kind of work anymore. I'm an academic now."
Suddenly, RAMBO and THE GENERAL are surrounded by Ninjas. This leads to a 20 minute fight scene in which RAMBO mercilessly slaughters the ninjas, sometimes using the bodies of dead ninjas as weapons against other ninjas.
After killing the final ninja, RAMBO hears a small cry from offscreen. He turns to see a nine-year-old boy in a wheelchair who is mortally wounded.
"Rambo," the child squeaks. "Avenge me!" He then melodramatically dies, lolling his tongue out and rolling his eyes into his head.
"Timmy!" RAMBO screams. "He was my best pupil!"
We are left to wonder why RAMBO, a university-level lecturer, was teaching a nine-year-old.
"See, Rambo!" THE GENERAL yells. "Now will you help us?"
"I'm not doing this for you," RAMBO says as he cradles Timmy's corpse. "I'm doing this ... for Timmy."
In the next scene, RAMBO is seated on a massive chopper on top of the Great Wall of China.
"I have to time this jump just right to end up in 1865," he says, to no one in particular.
He revs the chopper, and jumps from the wall, which explodes behind him. He lands in a dense, Southeast Asian jungle, but a caption at the bottom of the screen tells us it is Washington, D.C., 1865. RAMBO then spends the next 45 minutes fighting militiamen as he makes his way through the jungle. It is very important to note that AT NO POINT do steam-powered robots appear.
Finally, RAMBO makes his way to a bamboo hut. Sneaking inside, he finds ABRAHAM LINCOLN chained to the wall.
"Rambo!" LINCOLN says. "Thank God. Quick, emancipate me!"
RAMBO unchains LINCOLN and hands him a flamethrower. He and LINCOLN then spend another 30 minutes fighting their way through the jungle, eventually making their way to a waiting helicopter. As they are flown to safety, LINCOLN claps RAMBO on the back.
"Thank you, Rambo. How can I ever repay you?"
"Be best man at my wedding," RAMBO says with a smile.
Cut to a wedding scene, over which Guns N Roses' November Rain plays. RAMBO and LINCOLN wait smiling at the altar, as a woman we've never seen before approaches in a wedding dress.
As the minister pronounces RAMBO and the anonymous woman man and wife, the camera pans to the right to reveal Slash playing a screaming guitar solo. RAMBO and LINCOLN wink at each other, then high five.
Fade to black.
Note: As the credits roll, for no particular reason the blooper reel from Cannonball Run II is played.