This is one of those movies that isn't overly great, but I can't help but enjoy. Starts off somewhat similarly to The Blob (also from 1958), in which two teens try to convince the authorities of a giant spider residing in a cave on the outskirts of town. And once they see it, they believe.
In a scene somewhat like the cave scene from Night of the Lepus (1972), authorities witness the spider and gas the caves. Of course, the fun doesn't end there. We have a groovy scene where, as a band is playing some early rock 'n roll, the unconscious (everyone thought it was dead) spider wakes up, and strikes horror into both the students playing music and the town proper.
The movie, as a whole, is moderately unremarkable, really, especially considering the budget and effects of Tarantula (1955) were higher. Personally, I think this one has more spirit, though. Only problem I have, aside from some rather fake-looking webs, is one of the characters, Mike, comes across as an asshole half the time. Other than that, this is some solid fun, and even stands up upon a rewatch. One of the better creature features of the time, despite others' claims to the contrary. 7.5/10 (rounded down to 7/10 to fit site's format).