As the hero rides into the sunset, the screen 'fades to black'. [=the image gradually changes until the screen is completely black]
His voice 'faded' off into a whisper. = His voice 'faded' to a whisper.
We watched the ship gradually 'fade' from view as it sailed away.
(..) We open exterior outer space scenery. Calico comes for your Penny. And then you squish him. And as the tractor beam is pulling Penny and you to aliens' mother ship... ...we fade to black. And we have a great pop song for the end credits. Talk your people. We're ready to move on this. (..)2008 Bolt