One thing that amazed me in cannon is that how Crouch Jr. was able to impersonate someone for so long and not get caught. For example, someone was stealing stuff from Severus' supply of ingredients. Why didn't ask some house elves to hide in his office to see who it was? Another one of those great mysteries of cannon.
Author's Response: Yes, that definetly was a mystery. I figured Dumbledore must have had some idea but just let everything play out to see what happened.
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