While the first few films about space travel-primarily those by George Pal- were relatively serious and full of good intentions to get it right, the prime sources of inspiration for most of the films of the 1950s and early '60s-the first sci-fi boom-were not so much austere scientific journals and speculative studies, but rather the mad, bad pulp magazines of the 1930s, '40s, and '50s. These glorious mind-meddlers had already inspired movie serials...