It's an Iranian rite of summer: Islamic morality squads pressure women to keep their headscarves snug and coverings in place, and after a few extra tugs for modesty's sake the crackdown inevitably fades.
This year, however, Iran's summer fashion offensive appears bigger and more ominous, and has expanded the watch list to men's hairstyles and jewelry considered too Western.
No official explanation has appeared for the sterner approach this season. But it fits with the steady push by Iran's ruling theocracy to reel back the liberal fashion trends that began in the 1990s _ such as body-hugging coverings for women and earrings and tattoos for men _ and to sweep away non-Islamic influences in universities and cultural institutions.
The drive to turn back the clock _ part of what Iran calls a "moral security plan" _ also could reach deeper as the all-powerful clerics running Iran move to reinforce their authority.
The conservative forces around Supreme Leader Ayatollah Ali Khamenei have already struck back hard at President Mahmoud Ahmadinejad's attempts to expand his power base, and are expected to set a hard-line tone for parliamentary elections early next year.
Nearly two-thirds of Iran's parliament have signed a statement supporting the latest fight against "Western cultural invasion." It's blamed for such challenges to Islamic dress codes as women's headscarves pushed back and pants cropped short to show as much leg as possible.
Some 70,000 police officers have been deployed in Tehran this month to enforce the dress codes, the state news agency IRNA said.
"Confronting those who are not sufficiently veiled is a legitimate demand of the people," said Iran's police chief, Gen. Esmaeil Ahmadi Moghadam, who was added to the U.S. sanctions list earlier this month for his alleged role in the political clampdowns after Ahmadinejad's disputed re-election in 2009.
The fashion targets this year also include men's hairstyles and "un-Islamic" bling such as necklaces.
Last year, a fashion watchdog group gave the Culture Ministry a guide to acceptable men's haircuts. On the blacklist: ponytails, a spiked style known locally as the "rooster," and the retro "mullet" do, with its cropped front and cascading back.
"Of course there are people out there who would not like" young people's taste, said a man in his late 20s, who gave only his family name, Mohajer, as he browsed in a Tehran jewelry store. "But I cannot understand why I have to listen to them."
Breaking the fashion mold in Iran _ especially for men _ also has become a low-risk way to show support for the political opposition. Farhad, a 21-year-old student with shoulder-length hair, said he had once dyed portions of his locks green _ the color adopted as the symbol of the protesters after the elections two years ago.
"Young people are used to the crackdown on clothes every summer," said Farhad, who wouldn't give his last name for fear of reprisals from authorities. "But this year you get the feeling it's a bit more serious."
For men, the backlash has usually been just a warning to head straight to a barber or home to change outfits.
Women, however, often get a lecture on Islamic clothing and values, said Tehran Deputy Police Chief Ahmad Reza Radan.
"If they don't take action immediately and rectify the problem in their outfit, they will be arrested," he was quoted as saying by IRNA.
Then their families are asked to bring "appropriate" clothing to the police station. The detainees are freed only after signing a pledge "not in appear in public again like that," he said.
But the lines between fashionista and fashion outlaw keep shifting.
What was once common and seldom challenged _ such as tight-fitting and knee-length outer coverings on a woman _ could now bring rebuke, according to authorities. Earlier this month, a hard-line Friday prayers leader, Ahmad Khatami, said that even a woman's necklaces and bracelets should not be shown to men outside her immediate family.
There are no official reports on arrests linked to the fashion crackdown. But Tehran's deputy police chief Radan told state TV on Monday that authorities have notched up dozens of other busts: shutting down stores accused of selling revealing clothing.
Murphy reported from Dubai, United Arab Emirates.