be on the hook

1. To be held responsible (for something); to be obliged or committed (to something). I would think very carefully signing your name to those documents. If something goes wrong in the company, it could be you who's on the hook. I'm on the hook for nearly half a million dollars after my partner skipped town with the company's pension fund! Let me guess—insurance isn't going to pay for these damages, so you're on the hook for them, huh?

2. To be in a continually or indefinitely delayed condition or state. The suspect has been on the hook in the interrogation room for about 12 hours now. We're keeping him guessing in the hopes that he'll let some information slip. We've been on the hook for hours. I really wish they would just cancel our flight already. Normally, I would be home by now, but I'm still on the hook at the train station.