At the beginning of the movie some military personnel witness complete thermonuclear war from an underground military bunker. Two years later the world is completely fucked and an explosion in the base causes the four remaining soldiers to leave the base in their two gigantic 12-wheeled armored vehicles. They head out for a cross-country trip to Albany, where they've heard some recorded radio broadcasts.
Naturally along the way they run into various bad guys and mutated creatures, but not nearly as many as you'd expect. In fact the majority of the movie is pretty boring with just a lot of talking between the two leads: Jan-Michael Vincent and George Peppard (who has a terrible Southern accent).
The most fascinating thing to me about DAMNATION ALLEY is not really the movie itself (it's about as exciting as a lame sci-fi TV show episode), but the story behind the movie. I would love, love (!!!) to see a well researched documentary about the behind-the-scenes making and financing of this movie. According to IMDb, Wikipedia and a few other websites the budget for this film was $17M, which in 1976 (when it was made) was a sizable budget. The makers, 20th Century Fox, where also releasing one other science fiction film that year, but they didn't have as much confidence in it and only spent $11M (originally $8.25M but it increased due to delays) on it. That film was fucking STAR WARS!!!!!!!!!! Holy fuck! When you look at STAR WARS the story is impressive and it looks great, so what the f happened on the set of this clunker that cost $6M more and it still looks like hammered goat shit?! It boggles the mind.
Worth checking out, but trust me it's nothing special. I remember seeing it on TV when I was a kid and the armor-plated flesh-eating cockroaches scared the shit out of me. Watching it now thought it looks hilarious and you can even see the strings pulling the roach horde. LOL.