The original theatrical running time of Attack of the Crab Monsters was a cool 62 minutes. When low-budget films were sold to TV for syndication in the late 1950s and 1960s, local stations needed a roughly 75-minute film to fill a 90-minute slot, so distributors added prologues and text crawls (and sometimes newly shot footage with the film's original actors) to pad the running time. In the case of Attack of the Crab Monsters, two approaches seemed to have been taken. For some markets, a "crab attack" from late in the film was simply spliced at the beginning, prior to the credits, as a sort of "teaser." The official padding, however, consisted of a long text crawl which set up the film:
You are about to land in a lonely zone of terror...on an uncharted atoll in the Pacific! You are part of The Second Scientific Expedition dispatched to this mysterious bit of Coral reef and volcanic rock. The first group has disappeared without a trace! Your job is to find out why! There have been rumors about happenings way out beyond the laws of nature.
This was followed by further padding, consisting of stock footage of explosions, tidal waves and other disaster footage, along with a booming Biblical narration: "And the Lord said, 'I will destroy Man, whom I have created, from the face of the earth; both Man and Beast, and the creeping things and the fowls of the air; for it repenteth Me that I have made them.'"

Most of the cast of Attack of the Crab Monsters were veterans of other Roger Corman movies, and a few would later be considered part of his recurring but informal "stock company." Co-stars Richard Garland and Pamela Duncan also appeared the same year in Corman's The Undead (1957), for American International Pictures.

Richard Garland was the ex-husband of Beverly Garland, one of Roger Corman's favorite leading ladies; she played the lead in Swamp Women (1955), It Conquered the World (1956), Not of This Earth (1957), and Naked Paradise (1957), among others.

Mel Welles appeared in several Corman films; in fact his most well-known role was probably that of Gravis Mushnik, the owner of The Little Shop of Horrors (1960).

Russell Johnson proves to be a resourceful island hero in Attack of the Crab Monsters, but the similarities to his most famous role, that of "the Professor" Roy Hinkley on the TV series Gilligan's Island (1964-1966) end there; his character states at one point, "I'm no scientist." Prior to Crab Monsters, Johnson had already appeared in two big-budget science fiction films at Universal Pictures, It Came from Outer Space (1953), and This Island Earth (1955).

Like Russell Johnson, Attack of the Crab Monsters co-star (and part-time crab operator) Ed Nelson achieved his greatest fame in 1960s television, in particular a recurring role on the nighttime soap opera Peyton Place (1964-1969).

While some sources claim that a young Jack Nicholson was one of the people operating the crab from underneath the prop, there are more sources that deny this and say that the only two actors inside were Ed Nelson and Beach Dickerson.

The movie poster art for Attack of the Crab Monsters was quite spectacular, featuring a blonde in a bathing suit being gripped in the claw of a giant red crab. While the movie specified that there were only two crabs on the island, the poster art hinted at many more. The advertising tagline: "From the depths of the sea... A TIDAL WAVE OF TERROR!"

Corman's film directly inspired American poet Lawrence Raab to write a poem bearing the same name. Here is an excerpt:
Yes, we're way out there
on the edge of science, while the rest
of the island continues to disappear until

nothing's left except this
cliff in the middle of the ocean,
and you, in your bathing suit,
crouched behind the scuba tanks.
I'd like to tell you
not to be afraid, but I've lost

my voice. I'm not used to all these
legs, these claws, these feelers.
It's the old story, predictable
as fallout--the rearrangement of molecules.
from "Attack of the Crab Monsters" by Lawrence Raab (The Portable World, Penguin Books, 2000).

SOURCES:
How I Made a Hundred Movies in Hollywood and Never Lost a Dime by Roger Corman with Jim Jerome

The Films of Roger Corman by Alan Frank

The Films of Roger Corman: Brilliance on a Budget by Ed Naha

Return of the B Science Fiction and Horror Heroes by Tom Weaver

Attack of the Monster Movie makers: Interviews with 20 Genre Giants by Tom Weaver

Compiled by John M. Miller