From YouTube.
Nobody watches insurance ads; the throwaway put-down in the brief is more interesting than the ease it's describing.
Make the caveman real, modern, and wearily offended by the tagline.
The Stupid/Smart of it
Stupid: Anchoring a national insurance brand to sulking cavemen with hurt feelings — and running it for years.
Smart: A dead cliché becomes a character (surprising), and of course a caveman would resent that line (inevitable).
Built off GEICO's own tagline — the idea literally can't exist without that line, so no one else can run it. Earned.
A character format you can drop into any scene forever; the line entered everyday speech.
The device behind this one, from our library of ways in: