Gorgo (1961)

Other mistake: When the parent monster is just about to enter Piccadilly square, for a brief moment a view of a bus is shown. The writing on the bus is reversed.

sexxypeety

Revealing mistake: The sea creature Gorgo is paraded through the streets of London on a flatbed tractor trailer, and an off-screen American newsman announces the monster's arrival at Battersea Park, where it will be exhibited at Dorkin's Circus. The announcer introduces the creature's owners as they step from their motorcade, saying, "And our own Mr. Dorkin, of Dorkin's Circus, in the checkered suit." Problem is, Mr. Dorkin is wearing a plain gray flannel suit. Closeup shots of Mr. Dorkin over the next 40 seconds reveal that the suit is not checkered, not plaid, not striped, not patterned in any way at all. It's simply a plain gray suit. Apparently, the announcer's pre-recorded lines were never modified after changes were made in costuming. (00:34:05 - 00:35:00)

Charles Austin Miller

Radio Reporter: We're waiting at Battersea. Waiting. Hoping. Praying for a miracle. The entire electricity of all industrial London has been diverted to the wires surrounding the small animal's enclosure. Will it be enough? Will it be enough to stop the huge beast? Will the miracle be granted? Or will it be yet another of man's puny efforts to oppose this irresistible force of ancient nature?

Sam Slade: We might be able to catch it in the nets. But how do you propose to kill a thing like that?
Joe Ryan: Oh, I don't know. Dynamite, maybe?
Sam Slade: Ever stop to think what a thing like that might be worth alive?

Radio Reporter: Picadilly. The heart of London. Words can't describe it. There's been nothing like it, not even the worst of the Blitz! This section is complete shambles. People running, mad with fear.