On October 31, 2024, thousands of people descended upon O'Connell Street in Dublin, Ireland, to witness a Halloween parade. They waited, and waited some more. It took a while for the crowd to come to an uncomfortable realization: The parade was a hoax.

It started as a false advertisement on a website called My Spirit Halloween, but quickly gained traction online, spreading like wildfire on social media platforms like TikTok and Facebook. Part of the reason why it took off is that the site,"myspirithalloween.com," advertised multiple events, including some that were real. Its promotion of the fake Dublin parade also referenced the legitimate Irish performance group Macnas. To bolster its credibility, the website also included fake reviews, real photos from previous Macnas Halloween events, fake social media pages on Facebook, and other AI-generated text.

As the advertised start time of 7pm rolled around, thousands of people, some dressed in Halloween costumes, had gathered on O'Connell Street, despite the fact that there were no traditional signs of a parade. No streets had been blocked off, no police escorts, no signage, nothing. Videos and photos of the bewildered crowd flooded social media. The incident even disrupted Dublin's tram lines.

Irish police, in an attempt to disperse the crowd, issued a statement: “Please be advised that contrary to information being circulated online, no Halloween parade is scheduled to take place in Dublin City Centre this evening or tonight. All those gathered on O’Connell Street in expectation of such a parade are asked to disperse safely.”

Industry analysts believe the My Spirit Halloween website exists purely for the purpose of advertising revenue, and probably relies on AI-generated content to generate timely, relevant content. Just like the Spirit Halloween stores that the site references, this story popped up at just the right time to make an impact, then disappeared just as quickly.