Deep inside the earth lies a special place called Hell. The devils who work there have no corporeal existence, few memories, and count the passing time in aeons.

It's three days before the New Year, a new millennium even, when Number Three gets stuck with the assignment to conquer the soul of a fallen angel, an angel dismissed from Heavenly services who now lives as a mortal among humans.

Number Three, in a brand-new male body, is surprised to find the fallen angel is no other than his old nemesis, Number Sixteen. To make matters even more fantastic, the angel asks for Three's help in rescuing his ice cream parlour.

But while doing so, Number Three encounters strange new sensations, among them a genuine desire to actually help Angel and find out why he fell from Heaven. Angel is a very distracting assignment, and Three's emotions as well as his human body respond to the closeness between them. When it's time to wrap up his task, will Three be able to return to Hell and put Angel behind him?