spill one's guts

/S P IH1 L W AH0 N EH0 S G AH0 T S/
verb
  1. 1

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

    โ€œAt 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.โ€

  2. 2

    To vomit.

Source: https://en.wiktionary.org/wiki/spill%20one's%20guts