Full summary for Fathers and Sons:

In the 1970s, Voldemort terrorized wizarding Britain. He had some help, culled from the ranks of so-called halfbreeds: werewolves. Fenrir Greyback used the Dark Lord’s might, even as he used Fenrir, to achieve his own ends and build a pack with numbers so great they could conquer wizards. In the middle is Remus Lupin, torn between destroying one society and upholding another; the Longbottoms, Aurors in the political machine of Magical Law Enforcement and the Ministry at large and members of the Order of the Phoenix; and the Curentons, a family of activists who have suffered at Fenrir’s hands and continue their work even as they are rebuilding their lives.