I just finished watching this movie and I must admit I didn't have high hopes. To my pleasant surprise this turned out to be a quite good movie. It wasn't a great movie, but I am very glad I got to watch it! During a test of a low frequency transmitter two men and the transmitter disappear. A team is gathered to search the caves where the test took place. Caves that never before have been explored by man. But, what waits them below they could never imagine.This story turns out quite original and I think that is maybe what makes the movie so good. The script is far from perfect, but it works. The acting is probably the best with the whole movie. It is generally good. The cinematography could, however, been better. I find it too boring. It's too straight. Though they did a pretty good job in creating the atmosphere and the mood. There were some pretty chilling sequences.When it comes to effects what can you expect from a 1984 B-movie? Well, they did OK on most of it, except for the monster. It was actually pretty bad and in fact personally I think they should have cut the whole monster. They way I see it, it rather took then give anything to the movie.I can recommend this movie because of it's story. There are few cliché there. As for the rest of this movie it is OK, but nothing out of the ordinary. However, well worth to watch.

Sure, this is a B Movie but it is moody and creepy and worth a look. Haunting. I haven't seen it since it was on TV nearly 20 years ago and I can't forget it. The Lemurians are really unsettling weirdos. Sure, Timothy Bottoms is always a little suspicious but pretend he's a young George W. Bush and your path to movie fun is free and clear. It'll be great. Plus, Lisa Blount, can't go wrong there. Generally I'm against so-called reviews which say 'for what it is it's whatever' but in this case, when something does manage to be genuinely unsettling, I give it a go. Not much upsets or disturbs me, but this got under my skin and I think that's worth praising. Write your local congressperson or entertainment conglomerate and demand a North American DVD release. Now!

Contains some plot spoilers.I desperately tried to like this having first seen it aged eight, but what seemed exciting / scary back then, I find pretty lame now. It's in the style of Raiders of the Lost Ark or Romancing the Stone, but not half as good. Set in Central America (not in South America, where it claims Belize is ) the story follows the US Army setting up a low-frequency transmitter as a navigational aid to subs. As a precaution this 'beacon' is to be hidden deep underground and to help locate a suitable place is elite mercenary and caveman Rupert Wolfson. When men operating the transmitter mysteriously disappear, `Wolf' and some anthropologists help in the search which takes them deep into the mountain. Here they encounter unforeseen perils, including a race of temperamental albinos. Actually filmed in Alabama and Tennessee (Cathedral & Cumberland Caverns respectively) this suffers from dreadful acting and screenplay, plus lack of imagination as the 'mystery' unfolds (not to mention numerous continuity & editing errors) An atmosphere of intrigue and ambiguous wonder is created to (almost) good effect at the beginning, with the opening monologue discussing unexplored wonders of the Earth accompanied by eerie music. This ambience is lost after some badly directed action and almost ruins the following helicopter distorted lens sequence, meandering us through the unwelcoming landscape like a drunkard. `2001'-style wonder is paired with suspense as we enter the caverns, combining some good cave locations with matte artwork and photography. But the camera seems more interested in what our characters are doing. Before long the low budget is apparent and aside from some interesting monsters, we're treated to silly sets and costumes. Characterisation is based on racial stereotypes and the general level of stupidity of that person. Take our main character: he is suave Englishman Wolfson, acting as a consultant for the army; an expertfighter and all around good-guy. No personality flaws, only bad dresssense. Two ugly English (natch) play scientists who are specifically there to die. The female lead (obligatory love interest) is talkie (but not outspoken) Leslie. Working with the Anthropologists she helps extract long-dead remains but will scream when faced with a fresh one. Not too bright. The main American contingent play embarrassingly inept and unprofessional soldiers obsessed with working the transmitter as if their lives depended on it. Wolf's friend George's only importance to the plot is to tell Wolf about the mission. He is a lieutenant and an idiot. There are also several local Latin-Americans assisting the US, one is accident-prone Santos who acts as a plot device to attract the monsters. Acting is at best poor and veteran Robert Powell doesn't even try to get to grips with his (admittedly awful) script. Apparently the main script was being rewritten every day during the shoot and it shows! There are some good `Predator'-style effects as the humans are viewed as a pink glow through the Lemurians' eyes, but their rock-shattering scream was unconvincing. I did like the idea that the Lemurians are sensitive to ultra-sonic waves though. The plot badly loses its way. The buildup is painfully slow and when the 'mystery' is finally resolved, it's a real anti-climax (not giving anything away, let's say not exactly a Close Encounters moment) The idea of discovering creatures deep inside a tropical mountain landscape appealed to me, but `Secrets of the Phantom Caverns' is a letdown. Underground albinos!

The idea of making a film about the secrets and wonders of inside the Earth sounds like good idea for a movie but this movie just can't seem to deliver.The actors are bareable(well sort of)except for the main charecter who is just as way to smug.As far as special effects and set the crew did a okay job.And the plot would be better if there were more creatures and stuff and less of a boring,tedious buildup.