spill one's guts

verb2

1. •
   (slang) To confess, or to divulge secrets, typically speaking freely and at length after a change of motive or an incentive.

   • At first, the suspect would not tell us anything about the other participants in the crime. But after being offered a deal, he spilled his guts.
2. •
   (slang) To vomit.

   • He suddenly wanted to vomit, to spill his guts right here on Lake Street in front of the thousands watching. — 1994