easy person to hide from. Dumbledore told them that their best chance was the Fidelius Charm."

 "How does that work?" said Madam Rosmerta, breathless with interest. Professor Flitwick cleared his throat. 

"An immensely complex spell," he said squeakily, "involving the magical concealment of a secret inside a single, living soul. The information is hidden inside the chosen person, or Secret-Keeper, and is henceforth impossible to find -- unless, of course, the Secret-Keeper chooses to divulge it. As long as the Secret-Keeper refused to speak, You-Know-Who could search the village where Lily and James were staying for years and never find them, not even if he had his nose pressed against their sitting room window!"

 "So Black was the Potters' Secret-Keeper?" whispered Madam Rosmerta. 

"Naturally," said Professor McGonagall. "James Potter told Dumbledore that Black would die rather than tell where they were, that Black was planning to go into hiding himself... and yet, Dumbledore remained worried. I remember him offering to be the Potters' Secret-Keeper himself." 

"He suspected Black?" gasped Madam Rosmerta.

 "He was sure that somebody close to the Potters had been keeping You-Know-Who informed of their movements," said Professor McGonagall darkly. "Indeed, he had suspected for some time that someone on our side had turned traitor and was passing a lot of information to You-Know-Who." 

"But James Potter insisted on using Black?" 

"He did," said Fudge heavily. "And then, barely a week after the Fidelius Charm had been performed --" "Black betrayed them?" breathed Madam Rosmerta. 

"He did indeed. Black was tired of his double-agent role, he was ready to declare his support openly for You-Know-Who, and he seems to have planned this for the moment of the Potters' death. But, as we all know,