The Mystery of the Talking Elevator has been solved — we think.

TTC passengers taking an elevator at Dundas West station were treated on the passenger assistance intercom to an audio recording of Inferno, the fourth novel in author Dan Brown’s thriller series popularized by Tom Hanks’ film adaptations.

Was this supernatural, or simply the work of a fan?

“It’s a bit of a strange situation,” said TTC spokesperson Kadeem Griffiths.

The video of the talking elevator was posted on YouTube and Twitter by Michelle Porter on Wednesday. She said she had been sitting on the platform at the station around 6:30 p.m. when she heard a voice. She followed the source of the disembodied voice to the elevator speaker.

Her video was shared further on Reddit, where other users used their detective skills to suggest theories about might have happened.

One was that the literary stylings of Dan Brown might be the default audio test file for the system. Another was the thought that a security guard listening to the audio book might have left the microphone on.

Griffiths said the clues led them to believe the second theory is the answer. TTC fare collectors sitting in the booth in the station are allowed to play podcasts, music or audiobooks at a low volume to keep themselves occupied while on shift.

A collector likely answered a call from that elevator and then forgot to close the line after the conversation with the passenger had been completed, Griffiths said, so the gripping tales of professor Robert Langdon ended up being broadcast far beyond the four walls of the collector’s booth.

Griffiths wasn’t sure exactly how long the audio continued in the elevator. He said at some point the collector must have noticed and closed the line. As of Thursday morning, the elevator speaker is silent and free of thriller narratives of any kind, he said.

Since collectors are allowed to listen to entertainment on shift, and this seems to have been an honest mistake, Griffiths said there would be no repercussions for the collector.

Griffiths said he couldn’t speak to the literary taste of the collector, as he’s never read the book himself: “It’s not really my style.”

Of course, there were other theories among the TTC employees: the TTC customer service Twitter responded to the original Twitter thread with assurances that they had “got in touch with a lead demon in the area, and it appears a ghost was taking a break near an intercom speaker and left a switch flipped — no actual possession involved. The situation should be resolved.”