A mysterious callout, a secret event, and a frustrated cafe owner. It sounds like the makings of a Coen Brothers film, but it’s all too real for Melbourne-based fans of folkster Bon Iver and hospitality manager Robin Shepherd.

Bon Iver took to social media last night to issue a series of posts advertising various addresses in cities around the world, including Melbourne. The post included the date ‘September 29’, the time 6:30pm, and the address 121 Johnston St, Fitzroy.

Fans were immediately whipped up into a frenzy, taking to Reddit to speculate about what could be happening at this address. The posts included the artwork for Bon Iver’s forthcoming album, 22, A Million, suggesting the addresses could be hosting a listening party.

Others who were more hopeful suggested there could be a guerrilla gig happening, though staging gigs in Melbourne, Paris, Amsterdam, and several other cities would require a great deal of air travel for singer-songwriter Justin Vernon.

The other issue is that the Melbourne venue supposedly holding this listening party, the Sir Charles cafe located on 121 Johnston St, has no idea what’s going on, despite a cryptic mural appearing on the wall outside the cafe.

“Sir Charles cafe, it’s fantastic, but we’re not hosting Bon Iver,” manager Robin Shepherd told AAP. “I’ve been sitting here trying to do paperwork. I’m waiting for a call from a supplier and every person phoning up (is asking) ‘Bon Iver?'”

“I just called the cafe. The owner is getting swamped by non-stop calls. He said he’s going to turn off the phone and it’s probably somewhere else,” one fan wrote on social media, echoing the comments of several others.

Speaking to AAP, Mr Shepherd suggested it could be that the wrong address was included in the post and an event could be taking place at one of the area’s nearby live music venues.

Some fans on Reddit have speculated that the correct address could be 141 Johnston St in Fitzroy. However, Bon Iver’s Australian label has confirmed to Tone Deaf the correct address is indeed 121 Johnston Street.

“The phone did not stop ringing. Everytime I hung up, it rang,” Shepherd, chief of the hospitality group that owns Sir Charles, told Broadsheet. “I had so many funny conversations with people.”

“I started answering the phone, ‘Bon Iver Ticketing Agency’? One girl gave me the full rundown on who Bon Iver is.” According to Shepherd, Sir Charles may extend its hours to remain open on Thursday night, though he’s not sure just yet.

So it looks like we still have some unanswered questions about just what is happening at 121 Johnston Street in Fitzroy tonight, but we know for sure this is where it’s taking place, so you can stop calling the cafe owner.