What Would Happen if a Black Hole Invaded Our Solar System?

If a black hole stood between us and our sun, we would see like a black circle with a bright string around it. And then that ring would sort of merge with the sun and kind of distort the light around it. It reminds me actually of a great science fiction book I read. Parahelian by Greg Egan retalks about what happens when a black hole enters our solar system. Even before it made an impressive distortion of the sun's light, it'd be bad news.