New York transport officials were impressed when the hip-hop clothing label Akademiks announced that it wanted to buy advertisements on the sides of buses in the city, promoting the benefits of literacy.
But it turned out that the benefits in question weren't the ones the authorities had in mind.
The Metropolitan Transit Authority vowed yesterday to start removing the adverts after being informed that the slogan plastered over 200 city buses - "Read books, get brain" - refers to a slang term for oral sex.
"To me, and I believe to everyone else, while it was done by a clothing line, it would give the impression that it was also promoting reading and literacy," MTA spokesman Tom Kelly said. "It's easy enough to understand how that would get by based upon someone not knowing the expression."
Anthony Harrison, Akademiks' advertising designer, told the New York Daily News he had been fully aware of the connotations of the phrase "get brain".
"We knew this," he said. "It's coded language, city slang. Teens know what it means but the general public doesn't."
The adverts were a semi-public private joke between the company and its youth market, he argued - and in any case he doubted the slogan would be taken seriously even by those who understood it.
"I don't think any kid is going to say, 'If I read A Tale of Two Cities, I'm going to get sex,'" he said.
"They aren't stupid. We were trying to make education relevant in the sea of everything going on now."
But Mr Kelly argued that the ads, one of which shows a woman kneeling with an open book, were demeaning.
"It's sad that a company and its advertising agency would appear to be promoting a good cause while instead using vulgar street phrases to demean women," he said.
A further hazard of the campaign was highlighted by Bronx high school teacher Jim Mills, a rare instance of an adult who understood the reference: he told the Daily News he nearly drove his car into the sidewalk when he saw one of the posters on the side of a bus last week.
But the MTA's embarrassment was moderated somewhat by the fact that, according to Akademiks, the ads also appear on buses and bus shelters in Miami, Chicago, Los Angeles, Detroit, San Francisco and Philadelphia. Until yesterday, at least, none of them had figured it out either.