Lord Malfoy has been working for the department of mysteries since the Battle of Hogwarts in May of 1898. He proved his worth as a spy and double agent, and has been roundly celebrated as one of the Golden Quartet. Draco has never been satisfied, however, that the fifth member of their group was hidden from the public, and even less satisfied that no one in magical London has set eyes on Hermione Granger since the day after the battle, when she disappeared from St. Mungo’s.
Now, in May of 1910, the muggle King Edward VII, has been killed by magic and Lord Draco Malfoy finds a surprise awaiting him when he consults with an expert at the British Museum while on the trail of the killers.
Works somewhat within canon, books 1-4, if the books were set a hundred years before they were, then diverges.