I'll be darned!
(Well,) I'll be darned!
old-fashioned An expression of surprise or astonishment, especially regarding some recent revelation. A: "You know, if you run your washing machine at night you can save a lot of money on your electric bill." B: "I'll be darned, I didn't know that!" Well, I'll be darned! Who knew so many people would show up to see our concert?
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
I’ll be ˈdarned!(spoken, especially American English) used to show that you are surprised about something: Well, I’ll be darned! Isn’t that Lisa over there?
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