all bets are off
1. That which seemed certain or foreseeable in the future is now completely unpredictable. The team seemed poised for a deep playoff run, but now that their star player is injured, all bets are off.
2. Referring to an agreement that has broken down, been reneged upon, or is no longer valid. All bets are off on the proposed tax measure, as members in congress have failed to come up with a bipartisan solution.