People are still saying there's a man trapped inside the Chicago bean

"I am happy to confirm that a man has not been trapped inside Cloud Gate (aka ‘the Bean’) for the past 21 years. In fact, the man was freed years ago," So says Brendan Reilly, the alderman for Chicago’s 42nd ward. But can he be sure? Have the city authorities opened up the sculpture to check, or are they being swayed by 'Big Bean Media'.

That's the accusation from a group called the Man in Bean Coalition, which is standing by its absurdist claim that a baby was imprisoned inside Anish Kapoor's large mirrored legume while it was in construction back in 2004. That might seem ridiculous, but it's the perfect piece of performance art for our time, and other artists and brands are getting involved.

Art and protest go hand in hand, as demonstrated by various famous artwork attacks. But Man in Bean has caught the public imagination. Dressed in black, the Man in Bean Coalition spent several days protesting at sculpture late last month. They now have over 35K followers on Instagram, and the story has been picked up by media the world over (only to cast ridicule and cover up the truth, of course).

The group alleges that in 2004, the artist Anish Kapoor stole a baby and put it inside the bean, where it has grown up in isolation. They say the walls of the sculpture are a one-way mirror, allowing the man, now 21, to see out while remaining undetected by passersby – unless you look at the sculpture from a certain angle just as the light hits it in the right way, in which case a faint outline can be seen... apparently.

Despite taking the prank in good humour, Reilly appears to be getting tired of it. "I appreciate light-hearted parody as much as the next guy, and I’ve always welcomed public engagement. However, this online hoax has led to a heavy uptick in calls to my office," his statement continued.

“Unfortunately, answering the heavy volume of calls regarding this hoax is ultimately a distraction for my office from the real work we do for the 42nd Ward and City of Chicago each day.”

Anish Kapoor hasn't commented on the stunt, but his sworn adversary, the artist Stuart Semple, is loving it. He's advertising AirB&Bean stays in "a place where art, mystery, and polished stainless steel collide," and from where guests can "see the city from every angle without leaving your seat, thanks to the Bean’s state-of-the-art one-way mirror shell". For $10, you'll get a signed and numbered 'Key to the Bean' and some jellybeans.

Businesses are joining in to keep the prank going too. The Chicago pizza purveyor Lou Malnati's commented on Instagram: “Throughout the years, many of our drivers have delivered to [the man in the bean]. He is registered in our system as 'First name: Man in the, Last name: Bean Please free m'. Unfortunately, our system has a character limit and would not allow him to fill out the rest.”