Families in Scotland were expecting to taste chocolate treats and observe “optical marvels” at a Willy Wonka-themed event in Glasgow this past weekend. Instead, they got a couple of jelly beans, a short walk around a nearly empty warehouse and a visit from police officers.

The event, Willy’s Chocolate Experience, scheduled for Feb. 24 and 25, promised on event listing websites to include chocolate fountains, performances by Oompa Loompas and interactive experiences inspired by scenes from Roald Dahl’s book “Charlie and the Chocolate Factory.”

One father, Stuart Sinclair, drove two hours from Dundee to take his three children to the event. “There was maybe 20 chairs, a couple of tables and a half-inflated bouncy castle,” he said.

Mr. Sinclair said that he paid 35 pounds, or about $44, per ticket for his two sons, aged 10 and 11, and his daughter, 4, who was dressed in a Willy Wonka costume and had told her preschool teachers how excited she was to go to the event.

“The children got two jelly beans each,” Mr. Sinclair said. “And then they got a half a cup of lemonade.”

Families had booked time slots to enter the venue every 15 minutes and were greeted by rows of unadorned tables and walls of black fabric separating one sparsely decorated space from another.

“As soon as they walked in the door, they were like, ‘wow,’ just shaking their heads and totally in disbelief of how bad it was,” Mr. Sinclair said.

Alana Lockens, of Hamilton, said that after she had bought tickets, she noticed the event website had been updated with a legal warning to say that it was not related to the Wonka franchise, which is owned by Warner Bros. She grew concerned it was a scam and was initially relieved to arrive and see an actual event taking place.

“I can laugh about it now, but initially I just thought it looked ridiculous,” said Ms. Lockens, who went with her ex-husband, a friend and her two children. “It was so poorly done considering how much the tickets had cost us.”

Facing crowds of disappointed families, event organizers abruptly canceled the event Saturday afternoon.

Police Scotland said that officers were called after the event was canceled, but that the police determined they were not needed. It was not clear who called the police.

The event organizer, the House of Illuminati, addressed the complaints on Saturday, saying in a statement that it recognized the event was a disappointment and that it should have canceled it earlier. “We fully apologize for what has happened and will be giving full refunds to each and every person that purchased tickets,” the company said in a statement on its Facebook page, which has since been removed.

The House of Illuminati did not respond to requests for comment.

The event took place at Box Hub, an event space in Glasgow.

Matt Waterfield, the operations manager for Box Hub, said in an email that the House of Illuminati approached him in early January and that the company was entirely responsible for the marketing, promotion and operation of the event. “They dressed the venue on Friday,” he said. “The result was incredibly underwhelming.”

“We are fully on side with the many outraged customers and truly hope that House of Illuminati refunds these families as promised,” he said.

Families who attended the experience and people hired to work at it gathered in a Facebook group to complain about what had happened and to discuss how it would be set right.

Jenny Fogarty, who was hired to play an Oompa Loompa, told The Scotsman that she was given a 15-page script to read the night before the event began and that she received her costume an hour before families arrived.

“The wigs were very cheap,” Ms. Fogarty said. “We were just handed an Amazon box that probably arrived that morning.”

Ms. Fogarty said that she was told she would be paid £16.66 an hour, but that she had not been paid yet.

The event was marketed like immersive experiences that have appeared in cities across the world in the last two decades, such as the Museum of Ice Cream in New York and “Van Gogh: The Immersive Experience.”

The event’s website built on that suggestion but also hinted that the experience might be of questionable quality.

It promised “a journey filled with delicious treats, enchanting adventures, and moments worth capturing,” and it included elaborate, candy-colored illustrations. Those illustrations were marred by unusual misspellings and phrases, including: “a pasadise of sweet teats” and “exarserdray lollipops.”

Mr. Sinclair said that although his family was disappointed by Willy’s Chocolate Experience, he and his children still made the most of their day in Glasgow, taking his daughter to make her first teddy bear at a Build-a-Bear workshop.

“The worst part of all,” Mr. Sinclair said, “there was no chocolate.”