Upon leaving Blood Island, the ship carrying Dr. Bill Foster (John Ashley), Sheila Willard, her father and Carlos Lopez explodes and sinks after mutated "chlorophyll creature" Don Ramon Lopez (the titular "Beast") is found secreted on board and goes on a rampage, destroying the ship.

When Foster and Russell arrive on the island, they find the natives in a state of fear, believing that the old Lopez mansion is cursed.

With the village headman Ramu (Alfonso Carvajal) and the ship's captain (played by co-producer Beverly Miller), they search the house and find Razak (Bruno Punzalan) alive.

The "green men" return and after a fight, Myra is captured and taken to the evil Dr. Lorca (Eddie Garcia), who is still alive, but horribly scarred from his seeming demise in the earlier film.

He has removed Don Ramon's head and has attached it to machines, while the decapitated body remains strapped to a table.

[2]: 75 [6][time needed] To promote the film, the producers had fake $10 bills printed that folded in half, revealing an ad flier for Beast of Blood when opened.

[8] The featured review on IMDb states ""Beast of Blood" is far from horrible, but it's the weakest entry in the series, as it showing that the creators have milked the concept dry-in spite of some nice moments" [9]