An animated GIF (if it’s not moving for you, click the link) showing what it looks like if you’re looking at a black hole when a galaxy passes by in the background. Or at least when you move so that it looks like the galaxy is going by. The intense gravity of the black hole acts a lot like a lens made of rounded glass. The inverted image formed as the black hole approaches the light source is called an Einstein ring.
Image from Wikimedia Commons.