Harry Potter: Evil Rising

Sirius Black & Remus Lupin find their different worlds turned upside down when James and Lily Potter die, leaving custody of their son, Harry, to their care after their secret-keeper, Albus Dumbledore, is killed. Both men will be tested when, during Harry's school years, an evil will rise up that the wizarding world didn't expect. Loosely follows canon. Not always Harry centric.