2. Secret Keeper
This one has the potential of unraveling the whole series. When James and Lilly Potter went into hiding, they decided to turn down Dumbledore’s offer of becoming their Secret Keeper and choose Sirius Black, him being one of two James’ best friends. Just as the Fidelius Charm was about to be cast, Sirius suggests that perhaps he is too obvious of a choice and maybe Peter Pettigrew would be a better solution. All parties agree and Pettigrew become Potter family’s Secret Keeper. He later betrays them to Voldemort, who kills them and Harry Potter begins. Let’s rewind a bit. First of all, James, Sirius, Lupin, and Peter were inseparable during the Hogwarts years. Why suddenly is Sirius the “obvious choice” and Peter completely unsuspecting solution? Not to mention how such a cowardly person could become a member of Marauders and the Order of Phoenix and even be entrusted with such a secret. And even so, what if everyone knows Sirius is Potters’ Secret Keeper? The whole point of Fidelius Charm is that a person under it can’t be coerced into divulging the secret he’s sworn to keep. He can only disclose it voluntarily. So, even if Sirius is captured by Voldemort, Potters’ secret is perfectly safe.
