Tremors1990

[trapped on top of a boulder by a Graboid, Val, Earl, and Rhonda are thinking of explanations for where the creatures came from]

Valentine McKee:
[joking] I've got it: They're mutations caused by radiation. No, wait--the government made 'em. *Big* surprise for the Russians.

Rhonda LeBeck:
Well, there's nothing like them in the fossil record... Okay, so they predate the fossil record. [not buying it herself] That'd make them a couple of billion years old... and we've just never seen one until now. Right.

Earl Bassett:
I vote for outer space. No way these are local boys.