A new symbol has appeared in the kaleidoscopic jumble of neon signs that light up Sukhumvit Road, Bangkok's most international street. The sudden ubiquity of the five-pointed marijuana leaf, in lurid green, announces the spectacular boom there has been in weed-related businesses in Thailand since cannabis was decriminalised last June.
Walk two kilometres east of the BBC office in Bangkok, and you pass more than 40 dispensaries, selling potent marijuana flower buds and all the paraphernalia needed to smoke them.
Travel in the opposite direction, to the famous backpacker hangout of Khao San Road, and there is an entire marijuana-themed shopping mall, Plantopia, its shops half-hidden behind the haze of smoke created by customers trying out the product. The website Weed in Thailand lists more than 4,000 businesses across the country selling cannabis and its derivatives.
And this is Thailand, where until last June you could be jailed for five years just for possessing marijuana, up to 15 years for producing it; where other drug offences get the death penalty. The pace of change has been breathtaking.
"It is messy, but then this is Thailand, and without this sudden liberalisation I don't think it would have happened at all," says Kitty Chopaka, founder of Elevated Estate, a company that offers advice on the marijuana industry, and has been a part of the parliamentary committee trying to get the new regulations passed.
But this is not the kind of liberalisation long-term campaigners like her dreamed of.
"We need regulation. Spelling out what you can and cannot do," Ms Chopaka says. "It is causing a lot of confusion, a lot of people not knowing what they can do, what they can put money behind."
There are some rules in this apparent free-for-all, but they are being enforced haphazardly, if at all. Not all dispensaries have a licence, which they are required to have, and they are supposed to record the provenance of all their cannabis flowers and the personal details of every customer.
No products aside from the unprocessed flower are supposed to have more than 0.2 percent THC, the psychotropic chemical in cannabis, nor can they be sold online. Yet you can find suppliers offering potent weed brownies and gummies with high THC content online, with delivery to your door within an hour. Cannabis cannot be sold to anyone under 20 years old, but who is to know if the product is simply delivered by a motorbike courier?
There are restaurants serving marijuana-laced dishes, you can get marijuana tea, and marijuana ice-cream. Convenience stores are even selling weed-tinged drinking water. The police have admitted that they are so unsure of what is and is not legal they are enforcing very few rules around marijuana.
The new cannabis regime is a bit of a political accident. Anutin Charnvirakul, head of one of Thailand's larger political parties, made decriminalisation part of his manifesto for the 2019 election. It proved a vote-winner, mostly on the as-yet untested notion that cannabis could be a profitable alternative cash crop for poor farmers. As health minister in the new government, Mr Anutin prioritised getting it taken off the banned narcotics list as soon as possible to fulfil his election pledge.
But Thailand's parliament, a cauldron of competing interest groups, moves slowly. Cannabis was decriminalised before anyone had been able to write regulations to control the new business. And the planned new laws got bogged down by inter-party bickering. With another general election taking place in May, there is little chance of the law getting through the parliament before the end of the year. Already rival parties are warning of the dangers of unregulated weed, and threatening to re-criminalise it if they take power.
The future of this free-wheeling new industry is uncertain.
Tukta, a 21-year-old university student, jumped on the marijuana bandwagon last year, sinking more than one million baht ($30,000; £23,500) into a dispensary and coffee shop called The Herb Club in Bangkok's Klong Toei district. She sells 16 different grades of the cured flower, ranging from $10 to $80 a gram, but she worries about possible changes in the law. With so much competition from the many other dispensaries nearby, she says business is neither bad nor good.
"The price is falling because there's a glut of marijuana," Ms Chopaka says.
"There are a lot of illegal imports. We are growing strains from overseas, which need air-conditioning and lighting. We should look into developing strains that work for our climate to lower costs.
"We really need to go back to our old heritage, our old cultures. Because cannabis and Thais, Thailand, are very interwoven with each other."
For many Thais, who have grown up in a country which viewed all narcotics as a dangerous social evil, the dramatic flowering of the weed business since last year is bewildering. Yet the unforgiving official view of drugs is a relatively recent development.
Up until the late 1970s marijuana was widely cultivated by the hill tribes in northern Thailand, in the border area known as the Golden Triangle, which also used to be the source of much of the world's opium. Marijuana had also been used extensively as a herb and cooking ingredient in north-eastern Thailand.
When US soldiers arrived in the 1960s on "rest and recreation" breaks from fighting in the Vietnam War they discovered Thai stick, locally made from cured marijuana buds wrapped in leaves around a bamboo stick, like a fat cigar. The soldiers began shipping Thai marijuana back home in large quantities; along with Golden Triangle heroin it made up much of the narcotics flow going into the United States.
As the Vietnam War wound down, the US put pressure on Thailand to curb drug production. In 1979 Thailand passed a sweeping Narcotics Act, mandating harsh penalties for using and selling drugs, including the death sentence.
This coincided with a conservative backlash across South East Asia against permissive 1960s attitudes to drugs and sex, a reaction to the ganja-smoking backpackers travelling east along the "hippie trail". Thailand, Singapore and Malaysia all instructed their immigration officers to look out for hippies and bar them entry. At Singapore airport those with long hair were given a choice of a trip to the barber or being turned around. In Malaysia anyone with sufficiently suspect attributes would have the letters SHIT - suspected hippie in transit - stamped in their passports before being deported.
The Thai government was especially wary of alternative youth culture after it crushed a leftist student movement, killing dozens at Bangkok's Thammasat University in October 1976. Conservatives feared they might support a communist takeover in Thailand, as had just happened in neighbouring Laos, Cambodia and Vietnam.
Meanwhile a series of royally-sponsored crop substitution projects persuaded most hill tribes to stop cultivating opium and marijuana, and try coffee or macadamia nuts instead.
Since the 1990s cheap methamphetamines have poured into Thailand from war-torn areas of Myanmar. The ruinous social impact of meth addiction turned the Thai public even more firmly against drugs, and led to a brutal anti-drug campaign in 2003, in which at least 1,400 suspected users and dealers were gunned down.
It was the dire overcrowding in Thailand's prisons - three-quarters of them in for drug offences, many quite minor - that finally persuaded Thai officials to rethink their hardline approach, along with the realisation that marijuana's medicinal and therapeutic applications might be a valuable complement to the country's successful medical tourism industry. It was not much of a leap from that to see the potential in recreational marijuana too.
"Welcome to Amsterdam on steroids," booms Tom Kruesopon, the Thai entrepreneur known here as "Mr Weed" for his role in getting the drug laws liberalised, to a group of German tourists just off the plane, who cannot quite believe what they are seeing. Mr Kruesopon has opened a branch of the US cannabis store Cookies in Bangkok, and runs through the different strains of locally-grown marijuana, each in its own illuminated jar. Weed-themed underwear, slippers and t-shirts are on the shelves.
Perhaps it's the familiar tales of hapless Westerners locked up for decades in the Bangkok Hilton that make the visitors seem a bit hesitant. But Mr Kruesopon assures them they can no longer be arrested for buying and consuming any part of the marijuana plant in Thailand, though he does not allow smoking in his shop. He believes the business will continue to grow. "You're going to have a few billion-dollar companies here - I guarantee it." But he also accepts that better regulation is essential "otherwise you're going to kill the golden goose".
Outside of parliament public debate about cannabis is surprisingly muted.
"It's not ok. It's still like narcotics to me… Only the youngsters are using it more and those who have used it before are using it again," says a 32-year-old street vendor. But an older motorcycle taxi driver says legalising marijuana has neither helped nor harmed him: "We're not paying attention because we haven't been smoking pot. It doesn't matter to us anyway."
Some doctors have warned of the dangers of cannabis addiction, but for most Thais it pales beside the long-standing methamphetamine crisis. Dispensaries in central Bangkok say most of their customers are foreign tourists, not Thais. The most enthusiastic supporters of the new regime are the not insignificant numbers of people in Thailand who were already using marijuana regularly.
Self-styled "stoner" Amanda is one of them. She is happy to be able to cultivate the kinds of strains she likes at home, without fearing a knock on the door from the police. She has turned her small apartment into something like a shrine to the wonder-weed, filling her little bedroom balcony with reflective tents and powerful lights where she carefully tends seven plants. Her cat is no longer allowed in the bedroom.
"It was difficult at first. I had a lot to learn. I didn't get the temperature right at first, and using air-conditioning 24 hours a day, I need a humidifier. But it is so awesome this happened in Thailand. There are thousands of farms and dispensaries now, so many interesting people in the business."
For all the talk in Thai political parties of re-criminalising marijuana, or trying to restrict it to medical, rather than recreational use - a distinction those in the business say is almost impossible to make - it seems unlikely that after the last, crazy nine months the cork can be put back in the bottle. But where Thailand's free-wheeling marijuana industry goes from here is anybody's guess.