How should a bodhisattva respond to evil?

Not saying I have bodhicitta, one assumes I would know the answer if I did, but we can all emulate enlightening beings. What is the best way to respond to an nominally (nothing like that is innate) evil person doing evil (whatever you think amounts to that enough to at know not only that they should be stopped but that a lot hinges on it for other people) to get what they want? We vow to save all sentient beings: can we postpone it for some? Do we say "a Buddha would help you in your next life, but I cannot"? I suppose the answer is just to offer help to others first: after-all, we are all said to have undergone countless, trillions by trillions of lives, so no one life can be blamed for how it has suffered. But what if the evil doer turns to you for a better rebirth, after or even before their evil actions?