Sweet poison

Harry James Potter, the secret child no one has ever known about, was thrown into Azkanban for his precious brothers 'saftey' since he was a 'dangerous pychopath child' that was descended from the Lestranges. Obviously that wasn't true; but it stuck with everyone but the Lestranges, Blacks, Malfoy's, Zabini's Parkinson's, Harry and almost all of the Dark Side. Tom Riddle, is named Harry's father, since he was disowned by the Potter's and the others coulded afford to take care of him.
Friends with Draco Malfoy and the dangerous Slytherin gang, he leader of the Slytherin gang, raised in Azkanban by infamous Death-eaters, son of the Dark Lord; everyone feared him, just as he planned.