all bets are off

American  

[awl bets ahr awf, of] / ˈɔl ˈbɛts ˌɑr ˈɔf, ˈɒf /

idiom

1. (used when the outcome of a situation is too uncertain to predict).

   We have to make it to the meeting place by 5:30 or all bets are off.

   The individual ingredients may be safe, but once you mix them up into a brew, all bets are off.

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Etymology

Origin of all bets are off

First recorded in 1830–40, in reference to horse races

Example Sentences

But, he said, New York City is "a big place, it's a complicated place, and so, all bets are off about whether these things can happen or not".

From BBC

“Once the defendant testifies, all bets are off,” he said.

From Los Angeles Times

All bets are off as to who that might be.

From BBC

There is a sense that all bets are off.

From BBC

And I gotta take this to practice, and when I take that, all bets are off.

From Los Angeles Times