Remus Lupin, James Potter, Sirius Black and Peter Pettigrew knew every single passageway, nook and cranny of Hogwarts School for Witchcraft and Wizardry. Every single one. They could walk them in their sleep. They had even created a magical map with all of them.

Or so they thought.

Legends spoke of a secret tunnel that beheld a mysterious cloaked figure one of spellbinding beauty and the voice of an angel. Rumour has it: they roam the castle during the night, moving things, playing tricks and during the day they follow students, hiding behind corners, slipping into the cracks within the walls to stay out of view but they are there. They are always there.

Yet, it had been centuries since anyone had actually seen the figure or found the tunnel. So much so the legend had faded like smoke in the wind; a whisper forgotten and unheard of. However, for the select few that know of it, they never had much luck in finding the tunnel nor the cloaked figure nicknamed- The Rune.

A time came and The Rune grew more playful which eventually caught the attention of the boys who called themselves the Marauders. The boys now had a rival for all of their schemes and pranks but they were not prepared for defeat. Not from an old wives tale. Not from anything.

But did they really know exactly what they were getting into? It was crystal clear that they didn't. Remus Lupin especially didn't.