Creature from the Haunted Sea

Renzo Capetto

Mary-Belle Monahan

Sparks Moran / Agent XK150 / Narrator (as Edward Wain)

Pete Peterson Jr. (as Beech Dickerson)

Happy Jack Monahan

Rosina Perez

Mango Perez (as Sonia Noemi Gonzalez)

Gen. Tostada (as Edmundo Rivera Alvarez)

Cuban

Cuban

Cuban

Carmelita Rodriguez

Cuban

Agent XK-120 (Scenes added later for television showings) (uncredited)

Spy at the Bar (uncredited)

Man at Pay Phone (scene added later for television showings) (uncredited)

Shot back-to-back in Puerto Rico with The Last Woman on Earth (1960), using the same cast and crew, but not released until several months afterward.

Throughout the movie there are Spanish joke names such as Colonel Cabeza Grande (Big Head) and the reef is located on the Isla de Barracho (Island of the Drunk).

The scene of the Cuban military officers saluting as the little boat they are floating in sinks was not planned; it actually began sinking as they were completing the shot. Roger Corman told the actors to stand and salute as the boat sank and filmed every moment, later stating that it 'wasn't very deep' there. He also gave high praise for the Mexican actors that played the officers for taking direction so well.

At approximately 55 minutes, the young woman "Mango" is discovered coming out of the jungle, and again 5 seconds later.

When the monster attacks the ship at the end of the movie, you can see human skin where the costume sleeves didn't reach the gloves.

Renzo Capetto: You boys are getting careless. I told you to kill one, not two.

Sparks Moran: [narrating] Since taking up with Renzo, he's become a well-known dice-loader and murderer.

Sparks Moran: [to Mary-Belle] Listen, I have a plan. As soon as we get there, we'll wait for night and when Renzo isn't looking, we'll jump off and swim for shore through shark-infested waters so no one'll follow us, then we'll steal a sailing dingy and head for Brazil.