Tony Ferris (James Warren) is at the Institute of Oceanography talking to Dr. Joan Hunter (Lynne Roberts) and Mr. Lennox (Dayton Lummis). Ferris is looking to get funding for an expedition. Tony believes that sometime in the seventeenth century the Island of Port Royal sank to the bottom of the sea. In his research he has determined that, due to underwater seismic activity, Port Royal has, on occasion emerged from the sea for a short period of time before it once again descended into the murky depths. According to his calculations the island is due to surface again in two weeks. Ferris wants to investigate the phenomenon.

Tony is given the funds he needs for the expedition but he must take along Joan. The sexist finally agrees but he wants to pick the ship’s crew for the journey. There are stories that there is pirate treasure somewhere on the island and Tony doesn’t want to have problems with criminal treasure seekers. The last expedition he initiated had problems along just that line.

Unfortunately for Tony the criminal element is already aware of his plans. John Kolvac (Paul Cavanagh) breaks into Tony’s hotel room and steals the map of and directions to the island’s projected location. When Tony comes back to his room Kolvac hits him over the head and Tony ends up unconscious in the hospital. Kolvac, along with an old and devious cohort named Collins (William Schallert), steals the “Neptune”, the ship Tony hired for the journey. Not knowing all this has happened Joan innocently boards the ship.

When Tony finally wakes up in the hospital the ship is gone, Joan is gone and a storm is brewing. On a tip from a radio operator (Marjorie Stapp) Tony hires a daredevil airplane pilot, Jim Garry (House Peters Jr.), who is willing to fly him to the island’s coordinates through the raging storm. When the ship gets to the coordinates the island pops up as predicted. The crew on the ship head ashore to look for treasure locking Joan in her cabin, at least for a while.

At the same time the plane, having run out of gas, manages to get to the island not long after that. Tony’s number one mission is to find and save Joan. Since pirates be pirates, whether they are seventeenth century or modern, it takes no time at all for everyone to turn on everyone else. But time is ticking away fast and furious and no one knows when the island will once again sink to the bottom of the sea.

“Port Sinister” AKA “Beast of Paradise Isle” was released in 1953 and was directed by Harold Daniels. It is an obscure American low budget science fiction adventure film produced by RKO Radio.

The movie is rather plain for the most part. The plot is a decent one but execution of it was so-so. The main problem with the movie is it’s dark. It’s very hard to see what’s going on at night in a cave or at night anywhere on the island for that matter. That’s too bad. The opportunity for some cool visuals is lost. An atmosphere of a pirate town covered in seaweed and barnacles would add a lot to the movie.

What we do get is a badly maintained film that will probably never see a restoration. I think that if the film was in better shape it would have been a little more interesting and an overall better movie. Not great, but better. What I could see of the film was fun. Did I mention that there are giant man eating crabs in the movie? Of course they are back projection and there is only one of them, but it is a giant monster. There is also a lot of steam rising up so there is some atmosphere to tantalize you. I think that if the film did have some restoration done to it that it would blend in nicely with the standard “B” movie cult.