no shit

Interjection

1. Used other than figuratively or idiomatically: see no, shit.
2. (colloquial, vulgar) An exclamation of amazement or disbelief.
   • Well, no shit. What have we got here? A fucking comedian. Private Joker.1987 June 17, Stanley Kubrick, Michael Herr, Gustav Hasford, Full Metal Jacket, spoken by Gunnery Sergeant Hartman (R. Lee Ermey), distributed by Warner Bros. Pictures

   Synonyms:

   no kidding, no way

3. (colloquial, derogatory, often, sarcastic, vulgar) An ironic response to a statement of the obvious.
   • LAPD Operator: Attention, whoever you are: this frequency is reserved for emergency calls only.
     John McClane: No fuckin' shit, lady! Do I sound like I'm orderin' a pizza?!1988, Die Hard, spoken by John McClane (Bruce Willis)

   Synonyms:

   really, oh really, you don't say