After the success of "Godzilla" in 1956, Japan's Toho Studios cranked out a slew of popular kaiju (monster) films featuring the rampaging lizard king and his gargantuan cohorts.
Among the innumerable '60s installments in this series is "Godzilla Vs. Monster Zero." While it's not the best of the Japanese monster flicks (check out "Godzilla" or "Destroy All Monsters" for that honor), it contains most of the elements that made this film form so appealing to the average 5- to 12-year-old boy.
As usual, the plot is pretty far-fetched. Aliens from Planet X trick the gullible earthlings into trading Godzilla and Rodan (a giant reptilian bird) for a bogus disease-curing formula. Through a mind-control mechanism, the aliens then turn the two beasts and Monster Zero (a notorious three-headed dragon) against the Japanese. Result: the freedom--if not the survival--of the human race hangs in the balance.
Interestingly enough, bad guys aren't always bad guys in Japanese monster movies. In character switches worthy of the World Wrestling Federation, Godzilla and Rodan--who began their careers as societal menaces--are cast as more benevolent sorts in this film.