In the spirit of Godzilla vs. King Kong (with a hint of alternate-history pulp-fictioner Harry Turtledove), 1979's freshly reissued G.I. Samurai provides an answer to one of those unlikely nerdy teenage what-ifs: What would happen if a modern military force went toe-to-tabi-clad-toe with a Japanese samurai army? Stalwart Lt. Iba (martial-arts-flick legend Sonny Chiba) gets to find out as a detachment of contemporary Japanese Self-Defense Force soldiers (complete with machine guns, mortars, a tank, and a helicopter) finds itself mysteriously transported four centuries back in time to the feudal Warring States period of Japan. After a few one-sided skirmishes with wary samurai, Iba joins forces with ambitious Kagetora (mustachioed scene stealer Isao Natsuyagi). With Iba's advanced weaponry, Kagetora can consolidate power; if Kagetora takes over, Iba somehow reasons, history will change and he and his men will get to go home. Or something like that.
Early in the going, G.I. Samurai (also known as Time Slip) is full of the kind of flat spots, bad acting, and goofy dialogue familiar to fans of Mystery Science Theatre 3000; the special effects that accompany the JSDF soldiers' trip back in time are superlatively crappy, as is the late- ‘70s FM-rock score. Once the story gets rolling, however, the film proves itself surprisingly earnest and ambitious, detailing the effects of exile in time on the various JSDF troops, including Iba, who is having a much easier time adapting to an era of constant warfare than his long-haired grunts. And ridiculous as the film's concept is, the action is no joke. The central battle sequence alone takes up an entire reel of smoke and carnage as Iba and his men discover that they may have the samurai outgunned, but outthinking and outfighting them is another matter. So good-bad, for sure, but not as bad as you might think.