Rupert has to have a start somewhere. Maybe it'll be somewhere sometime later. For now, you're going to start in a random place in his life. It's not a great story, but one could make it worse.
Rupert lives in Gothic City. Gothic City is a strange place, located on the edge of a mountain, with fields down the mountain for growing and raising food, and a circular city at the top, centered on a cathedral. The whole city is surrounded by a wall, keeping it safe from invaders past, and keeping its current residents safe, for the most part. Rupert lived inside the wall, very close to it. He'd been able to buy his house cheap, as the city's main highway, designed only for bicycles, was built on top of the roofs of the houses around the edge of the city. The houses in Gothic City were mostly the same. Twenty or so townhouses, three stories each, all squished together. It wasn't bad living there, though the houses were a bit small. Most everybody was satisfied, and, if you had more money, you could buy a wider house or even two townhouses and smash the walls for more space.
That being said, Rupert left his house after grabbing his satchel and front-door keys, and walked to the subway station entrance, located a few blocks down in a block of shops, which looked similar to the townhomes. You have to look for the entrance. It looks like an ordinary storefront, though its only difference being its door bearing the logo of the rail network. He took the train straight to the city's library and town hall combo building.
Upon his arrival, he walked out into the main area outside of the subway station connected to the building. It looked like a mall, but with only three big storefronts, and a pair of escalators, an elevator from the 1940s, and a set of stairs leading up to an exterior entrance. Rupert walked straight into the library.
The library had been ill-maintained. A fool in the government had forced the city to remodel the building in the 1960s, and the remodel had been abandoned. It had looked awful until someone in the 2010s had designed a remodel that was implemented, adding modern yet warm LED lighting and a somewhat modern design to it. Since the majority of it was underground, there weren't any windows, and it was very quiet.
Rupert had quite a ways to walk. He needed the archive. He'd been reading through the city's archive books, trying to find the missing link he needed to find the story behind the abandoned subway station that was intended to be the main subway station. There were thousands of these books, and no one ever read them, even though they contained the most extensive details of the history of that city.
Hours upon hours had been spent, reading through these books. Yes, the city was paying someone to slowly digitize them, but they'd barely gone through five percent of them. Rupert had gone through far more of them. He'd spent hours, searching each one for the reason why that station was closed. He'd spent far too much time on it, but nobody cared. He wanted an answer, and he was going to get it.
After all, the city liked to keep this a secret. They treated it like it would cause a big collapse. Rupert had no care about what the city claimed. They'd offered him lots of money to quit his research, but he'd declined.
He pulled a book off the shelf. However, he'd noticed one was missing. No one knew when the city had actually cut the station off for good, as most trains there were rerouted silently, and most people didn't notice. As a result, nobody knew the exact day, or even the year it was finally cut off. It seemed that Rupert had, in fact, figured something out. The book for the 14th to the 20th of July 1968 was missing.
He'd thought it'd be simple, but now he realized it'd be far harder to get to it. He also realized that the city had, in in its ordinary behavior, put this book in front of his face the whole time. Ever since he'd moved there, the city had had a vault in the library. This vault was supposedly accessible to the public, though they carefully guarded the code to it. You had to crack it yourself, and the hints given were so complicated, that no one even bothered with the two-hundred page file on how to decode it.
Rupert had found the lost link, right in front of his eyes, locked in a vault he couldn't access.