When somebody acts/does something which is sooo insane and legendary that no one can question it.
"Yo G, you see Fabian fall?" - T
"yer man, that was legendary..." - C
"Serious Guy" - T

by Connor D Scott December 3, 2008
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noun. A covert operative for the Central Intelligence Agency, MI6, and/or Mossad.

Or other unknown state and/or non-state operatives, seeking to maintain the status quo of the military industrial complex.
Mick: Hey man, who do you really think killed JFK?
Jack: Serious Fucking Guys man.
Mick: ye.
by BonerMasterMick2 May 7, 2021
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