Last month, I wrote up the presence of a Toynbee Tile in downtown Pittsburgh. Urban mysteries fascinate me, so we rented Resurrect Dead via Netflix. It's a documentary of these three guys obsessed with solving the mystery of who created the tiles and if he was still alive.
While the text on the Toynbees indicates a potentially mentally unstable person, the lead guy in the documentary also seems to be wrestling with his own demons of obsession too. The other two guys were a garden variety dork and nerd (my people). Together this nerd troika pieced together a 1983 Philadelphia Inquirer interview, a snippet from a David Mamet play, a Larry King interview, interviews with ham radio operators, on site viewings of hundreds of tiles across the United States (and sharing views of tiles in Chile and elsewhere in South America) to get to South 9th Street in Philadelphia.
At this specific address, they found evidence of a hermit who walled himself off from society -- literally, he put plywood on his windows and ran a 1 inch diameter metal bar through his door as an extra deadbolt. Interviews with his neighbors, humorous by themselves, revealed that "Sevy" (short for Severino) used to drive his car around at night and broadcast his manifestos that would come through their TV's. He also had no floorboards in the passenger side of his car -- perfect for surreptitiously laying tiles in urban settings at night.
But they never interviewed Sevy himself to confirm it, even with all the evidence they had, so it is still technically "unsolved". Sometimes the people chasing the mystery are as odd as the subject they are chasing.