Atom bomb test in Arctic awakens an ancient Rhedosaurus. Naturally being grumpy after his long nap, he takes his anger out on the eastern seaboard.
The grandpappy of all giant lizard flicks, and a pretty good one at that. Buoyed immeasurably by Kellaway's likable and unlucky paleontologist, and of course Ray Harryhausen's wonderful effects. The ending is a bit absurd, but Lee Van Cleef's bad-assery sells it. This is also the film with either the bravest or stupidist cop in all cinema, who, seeing the monster marauding his way through the Financial District, unloads his six-shot revolver at it before promptly being eaten. You see the same actor shortly after, only now with a rifle, so maybe the Rhedosaurus spat him out.
Note: The cast list given in most sources is missing some roles and confused on who played others. Supposedly "authoritative" sources like the American Film Insitute don't help. From the AFI film summary: "The character of the surviving seaman portrayed by Jack Pennick, who was listed as "Jacob" in the NYT and Variety reviews, was called "George LeMay" in the film." Do the people who work for the AFI even the watch movies that are their reason for existence? Arggghhh!