One renter moved into his apartment, only to discover far more than he anticipated underground.
Of course there couldn't be a secret dungeon complex under my bog-standard studio I rented for small money, that only happens in poorly-written movies.
Hang on a second...
This can't be true, that's definitely a staircase.
The presentation as a single imgur instance has a nice storytelling feel to it. It reads like a comic book or illustrated novel, alternating and linking text with images in chronological sequence. Notice, too, the closing text's narrative hook:
I'm debating my next move. More exploration needs to be done, but it's very scary living above it alone.
(thanks to Gothically-eyed Randy McCall)