The Monster That Challenged the World (a.k.a. The Jagged Edge and The Kraken) is a 1957 black-and-white science-fiction monster film from Gramercy Pictures, produced by Arthur Gardner, Jules V. Levy, and Arnold Laven (who also directed), and starring Tim Holt and Audrey Dalton. The film was distributed by United Artists on a double bill with The Vampire.
The film concerns an army of giant mollusks that emerge from California's Salton Sea.
The mollusks escape into an irrigation canal system, attacking livestock, a lock keeper, a trysting couple, and others. Navy divers locate a group of mollusks in the canal system, and use explosives to destroy them.
In the meantime, Gail is at the lab with her young daughter, Sandy (Mimi Gibson). Worried about the lab rabbits being cold in the lab's lowered temperature, Sandy surreptitiously turns up the thermostat. Twill calls the lab and gets no answer. He arrives and finds that the hatched mollusk has Gail and Sandy cornered in a closet, where they ran to escape from the monster. He fights it with lab chemicals and a CO2 fire extinguisher until other Navy personnel arrive and shoot the mollusk.
The story for The Monster That Challenged the World came from David Duncan, who also went on to pen screenplays for The Time Machine (1960) and Fantastic Voyage (1966). During production, Duncan's original work was titled The Jagged Edge, before the screenplay was renamed The Kraken. Prior to the film's release, it was once more retitled, this time to The Monster That Challenged the World.
Filming took place in 16 days on a budget of $200,000. A majority of the underwater scenes in the production were shot at Catalina Island off the coast of Los Angeles. Other primary filming locations included the Salton Sea, as well as Brawley and Barstow, California. The close-ups were later filmed in a tank filled with water and plastic seaweed.
In a 2016 interview, star Audrey Dalton recalled: "I thought it was a very interesting experience - as all my movies were in different ways. The director, Arnold Laven, had formed a production company with Jules Levy and Arthur Gardner. The monster stuff was fun, crouching behind a desk with a monster breaking down the wall. But you had to play it very straight. Once you start seeing the funny side of it, it doesn't work. Tim Holt had come out of retirement to do this movie. He was a quiet, very nice man - the most 'unactor' actor that I ever worked with. The film's poster features a woman in a bathing suit. People think it's me, but it was the actress whose character was drowned in the opening sequence. She's pulled into the water by the monster. We shot down on the beach for that. I think the rest of it was filmed along the California Aqueduct."
A TV Guide review of The Monster That Challenged the World noted, "Fine special effects help this film along by adding an atmosphere of impending danger." A later review by author Dave Sindelar of Fantastic Film Musings and Ramblings remarked: "For some reason, this fifties monster movie doesn't get much respect, but I think it holds up extraordinarily well. For one thing, I think the characters are unusually well drawn for this type of movie, and they're given a dimension and a sense of realness that adds a lot to the proceedings".
Respect for the "monster" also dominated a later review of The Monster That Challenged the World in the Video Movie Guide: "This late-1950s sci-fi programmer is set apart by only one thing: the giant monster, which is life-size (not a miniature), and given plenty of screen time."
As of 2015, the film was available on DVD as part of Metro-Goldwyn Mayer's Midnite Movies collection.
Note: The Monster That Challenged the World's Gramercy Pictures is not related to the former PolyGram division of the same name.