As most of Tokyo sleeps, men in rubber boots haggle over tuna in the halls of Tsukiji market.
The clang of a bell around 5.30am kicks off the action at the world's biggest fish emporium. Traders flash hand signs and bellow out prices as they buy and sell what will soon end up on plates in the Japanese capital and beyond.
In all, about US$18 million worth of fish, seafood and vegetables - over 2,900 tonnes - change hands each day at the market.
"Do you see how we use hand signs?" asks one bidder, seconds after another man violently rings the bell and starts yelling out bids. "This is exactly how people used to trade stocks in the old days."
Little has changed in the way business is done at Tsukiji since its opening in 1935. Now, almost 80 years later, the city plans to move the market to a new location and give the popular tourist draw what advocates say is a technological update. Not everyone is happy about the move away from prime real-estate in the centre of the metropolis.
Relocating the market and building to a modern facility about 40 per cent larger with state-of-the-art refrigeration will cost upwards of US$3.8 billion.
Watch: The world's largest fish market prepares for big move
The move, scheduled for March 2016, has been marred by revelations of soil contamination at the site, formerly a gas plant, about 2.3 kilometres away.
That has saddled Tokyo with more than US$500 million in clean-up costs at the less-than-central location. It is unclear what will happen to the current site beyond building a new road linking downtown with some 2020 Olympic Games venues.
Hiroyasu Ito of the Seafood Wholesalers' Association says the move is crucial for Tsukiji to handle modern-day demands for freshness.
"Railroad freight cars used to roll in to the market and unload fish and goods right here," he says, pointing to a large picture in his office that gives a bird's-eye view of Tsukiji's layout. "We don't use the rail cars any more. Now, refrigerated trucks drive around instead."
Key to ensuring perishable goods stay fresh is a so-called cold chain, which maintains produce at a consistent temperature until consumers buy it, something the market is ill-equipped to do, Ito says.
The move to a scrubbed-clean market is not popular with some shoppers. "The messy and crowded scenes at Tsukiji are what makes the place attractive," said out-of-town visitor Tetsuya Kojima, who added that he was unlikely to visit the new site.
Some of the old guard are not about to leave quietly either.
Union member Makoto Nakazawa, a leader in the fight to stop Tsukiji's move, lashes out at what he sees as profit trumping all else.
"Tokyo wants to move the market to satisfy the greed of real-estate interests here. I cannot think of another reason," says Nakazawa, who has organised small demonstrations in protest.
The 40 hectares of land earmarked for the new market is soaked with toxic chemicals, the legacy of its previous life as a gas plant.
Opponents have filed lawsuits over the city's purchase of the land without requiring Tokyo Gas to clean up its former site. That means taxpayers will shoulder the hefty 58.6 billion yen (HK$4.3 billion) clean-up.
"We are aware of a number of difficulties," says Masataka Shimura, a Tokyo official leading the new market project. "But we're still planning to do the move as scheduled."