Only recently have movie makers started to make movies like this again. This movie was one of the hidden gems of science fiction. The plot was basic, with interesting characters, and an exciting story line. One outstanding feature was that the hero was actually disabled. Try getting a script like that past producers in the 70's through the 90's! And he was very likable, dignified character. A team, your basic hero, the girl, and the preppy glory seeking antagonist, search for the girl's brother in a remote cave, and find a few surprises. The monster fungus is scary by any day's standards, due to proper directing techniques. The film works. And it leaves you with a sense of excitement and enjoyment. It is a truly fun movie.

This campy excursion into sci-fi horror is much more entertaining today than when it was first foisted upon unsuspecting, value-for- money-seeking audiences back in 1957. Of course its soap-suds special effects and papier-maché sets can only really be appreciated in their full glory in genuine Regalscope — which affords a better view of lovely Mala Powers and nice May Wynn too. Unknown Terror rates as a distinct cut above the usual Regalscope feature. One reason, of course, is that despite the CinemaScope process being here labeled "Regalscope", this is not entirely a Regal Films Production, but a co-production effort with an indie outfit called Emirau. True, there's still too much talk and too many static camera positions, and even the action scenes could stand a bit of trimming, but the heroine is a beauty and the climax comes across as pretty exciting too (even if the fungus does look a bit too much like soap- suds).

It's nice to see John Howard again after all these years. He hasn't aged much, but his acting hasn't improved a great deal either. Good to sight May Wynn too. She certainly makes a lithe native girl, though her role weighs in as not over-large and she is somewhat overshadowed by the stunningly attractive and entrancingly seductive Mala Powers.

Warren's direction can accurately be described as effective enough in the action spots. The cavern sets are certainly visually appealing. A bit of money has obviously been expended here, and that largess lends the whole film a fair degree of class. Other credits notch in as serviceable or better.

As others have noted, this is not great, but not terrible. There is something about it that just makes it fun to watch. I, too, remember it from my youth on Dr. Shock (a Philly-based horror movie show).

I recently scored a DVD copy of the film and thoroughly enjoyed it after a 35 year hiatus. I still enjoyed it.

It's one of those movies in which you can see that they spent some money on it, made sure to use real actors who were decent, write a decent script, and make sure they used good sets and locations.

Also, like others, the main thing I remember is the fungus. Oozing down cave walls, looking a bit like bath bubbles with an attitude! Fun stuff.