over a barrel

over a barrel {infml}
(helpless; in the power of your enemies, in someone's power; at a disadvantage; in a helpless or trapped position; not able to do anything about what happens to you) — в невыгодном, затруднительном или беспомощном положении; в идиотском положении; в ситуации вынужденного компромисса, в ситуации признания поражения

get/have sb over a barrel (to put someone in a very difficult situation in which they have no choice about what to do ) — поставить в безвыходное положение; связать по рукам и ногам; припереть к стене;| попасть в западню; оказаться в невыгодном положении.

Examples:

.....John is really over a barrel since he lost the only copy of the book he needed for his report
..... Well, I guess you boys think you've got your old mom over a barrel, huh? Well, we'll just see about that. (Mv: Malcolm in the Middle)