Better written than "The Night the World Exploded," "Creature With the Atom Brain," Twelve to the Moon," "The Deadly Mantis," "Beginning of the End, "The Black Scorpion" and "Fiend Without a Face;" better paced than any of those, plus "Kronos," "Spacemaster X-7," "Rodan" and "The H Man"; at least as well directed (by Fred Sears) as "Earth vs. the Flying Saucers," this movie gets most of its pans due to a ludicrous monster and some supporting actors better befitting a "Three Stooges" short. However, even the monster is better than pretty much anything Japan produced after its 50s "Golden Era". Besides, you pretty much cannot go wrong with Jeff Morrow and Mara Corday.
I wish the movie had included the occult legend of a "Stargate" at each of the poles. That would certainly explain how a creature could pass from an "anti-matter galaxy" and ours. Nonetheless, this scientific mumbo jumbo is far more convincing than the "Element 112" nonsense of "Night the World Exploded." Thanks to Morrow, Corday, Morris Ankrum and Fred Sears expert direction, ludicrous monster or not, the movie actually generates some fairly good suspense. I give "The Giant Claw" a "5".