quantum mechanics - How does Bell's theorem rule out the possibility of local hidden variables?

It seems to be common consensus that the world is non-deterministic and this is proved by Bell's theorem.

But even though Bell's experiments proved that the theory of quantum mechanics work, How does it prove the non-existent of local hidden variables?

Isn't it possible that there are hidden variables at work, and the results that were derived from these hidden variables coincide with the predictions of quantum mechanics?