Near dusk, on the shore of the Black Lake.
The powerful Water-Dividing Charm was still at work, parting the icy lake water to reveal a brightly lit construction site.
Several large tents, kept warm and bright by magic, served as the Marauders Power Company's Frontline Command Center.
Inside the main tent, the atmosphere was tense.
Sirius Black, the company's boss and Hogwarts' director of academic affairs, was holding a meeting with his legs crossed.
Remus Lupin, the project's chief engineer and head of Silvermane Academy, sat nearby.
The only people at the meeting were the two of them and the company's chief research and development engineers, Fred and George Weasley.
"...The Maze Core is nearly finished," Lupin reported, pointing at a glowing magical engineering blueprint on the table. "The Ancient Runes supplied by the Merpeople tribe have been installed too. The main work now is for your Research and Development Department to install and fine-tune the traps."
Sirius lifted his hot cocoa and blew on it, then asked in a very critical tone, "All right. So, you two geniuses from the Research and Development Department, how are your preparations coming along?"
"Reporting, Director Black!"
Fred immediately stood at attention and gave a passable military salute, but the chocolate at the corner of his mouth gave him away.
"We've completed the first-stage Basic Deterrence System!"
"There are stones that automatically sing off-key, seaweed that turns your hair rainbow-coloured if you touch it, and Filch's Howler Series Alarm Charms," George added proudly.
"Guaranteed to make anyone trying to sneak a peek feel thoroughly uncomfortable."
Sirius curled his lip.
"That's all? Not enough."
He set down his cocoa cup, which clinked softly against the table.
"I just received word that the people you'll be facing have changed."
"We were just about to report