As the numbers of Hell grew, so did its power. Threatened by this, Heaven made a truly heartless decision. That every year, they would send down an army, an Extermination, to ensure Hell and its sinners could never rise against them.

Hoping to end Heaven’s annual genocide with a more peaceful alternative, Charlie, the princess of Hell, set up the Hazbin Hotel, a place that aims to rehabilitate sinners so that can be accepted into heaven! With the help of her devoted manager and girlfriend, Vaggie, and their reluctant first patron, pornographic film actor Angel Dust, she is determined to make her dream become a reality.

Unfortunately, things didn't quite work out the way she had hoped as people find her belief in redemption to be laughable. Returning to the hotel lobby, Charlie slumps against the front door in defeat, only to suddenly hear someone knocking outside...