The story picks up from the time Harry celebrates killing Dumbledore. What Rowling mentions under Epilogue is disregarded. Voldemort is a good man. He is still alive because he made a new horcrux when he killed Severus Snape. Voldemort is reformed, becomes a good man and embraces Isläm.
With Harry Potter as Minister of Magic and Hermione Granger as Secretary of State, the Ministry has embarked upon a campaign to eliminate Magic. Hogwarts is closed. Use of Magic is forbidden by Law. Wizards are forced to purchase Rockindian corporations' products for day to day conveniences like mobile phones instead of owls. Can Draco, on the run at present, save the Wizardkind?