[1] A pirate ship, involved in 1588 battles on the side of the Spanish Armada, suffers extensive damage and must put into a village on the British coast for repairs.

This results in the villagers' sullen cooperation, but rumours and unrest begin to spread and soon the Spanish pirates find themselves facing a revolt.

"The idea was to release these bloody-but-not-too- bloody adventure films during school holidays, and they made a fortune on them," said Don Sharp, who would direct Devil Ship.

[3][4] Don Sharp had just directed his first feature for Hammer, Kiss of the Vampire and was invited back to work at the studio by Tony Hinds.

Little Boy Blue?’ So he asked me what colour I wanted and I told him grey, which he thought was dull and unthreatening until I reminded him that it was threatening enough for the Nazis!” ".

On the other side of the road council workers were starting to build a motorway so Sharp had the crew lay smoke to obscure trucks in the background.

[10] Sharp said, "The scaffolding went to the bottom and was there for two years with the company who owned the pit still charging hire for it!” [6] Lee wrote during filming that he thought the movie "will be a first class piece of overall entertainment — colourful and exciting.

"[11] In another letter he called Sharp "sone of the most talented and imaginative young directors to have appeared on the British scene for a long time....

I personally have never received better or more intelligent photographic coverage in any picture and, though I say it myself, had more chance to show what I can do with a really rougher part than I had in Blood River, where owing to the incompetence of the director, we were all fighting hard to get our faces anywhere near the camera.”[12] The film was released in the UK on a double bill with The Invicible Seven.

[13] Variety wrote "The production skills of Britain's Hammer Film artisans convert this otherwise routine adventure melodrama into a slightly better than average entry of its genre.

The solidity of these physical values, coupled with a dramatic concept that stresses action elements, should override to some _ extent certain story deficiencies and the obscurity of the players to Yank audiences and make the Columbia release a serviceable partner in an exploitation dualer for the maleoriented adventure market.

Hammer once announced it would make a biopic of the female pirate Anne Bonney to star Raquel Welch, Mistress of the Seas.