An abandoned former Boots store was raided by police, and once inside they discovered hundreds of cannabis plants inside.
Officers busted the building on Queen Street, in Burslem - on Monday, July 4, report Stoke-on-Trent Live.
And now, the city of Burslem has been dubbed the 'cannabis capital of Stoke-on-Trent '.
Staffordshire Police are now trying to find the gardeners and the brains behind the operation.
A police spokesman said: "We are investigating after approximately 500 cannabis plants were discovered inside a business property.
"Police forced entry into the building and once inside discovered a large-scale cannabis cultivation spanning several rooms and two floors. Western Power was called to attend due to an electricity bypass at the site."
They added: "Police are currently working to establish the offenders responsible for the grow and would like to speak to anyone with any information."
Witnesses should call the police on 101, quoting incident number 229 of July 4, or alternatively call Crimestoppers, anonymously, on 0800 555111.
This comes after three brazen criminals flogged cannabis sweets disguised as Nerds, Smarties and Millions through Snapchat and Instagram.
Reo Mangal, 24, Olivia Butler, 24, and Ceroan Mangal, 35, sent "dangerous edibles" containing THC through the post to addresses across the UK.
Meanwhile in May the Mayor of London, Sadiq Khan, announced he set up a new body to look at whether cannabis should be decriminalised in the UK.
The London mayor has established the capital’s first London Drugs Commission to “examine the effectiveness of our drugs laws on cannabis”.
However, Labour has distanced itself from the plans - with a spokesman saying the party "does not support changing the law on drugs".
And Home Secretary Priti Patel hit out at this, tweeting: "Sadiq Khan's time would be better spent focusing on knife and drug crime in London.
“The Mayor has no powers to legalise drugs. They ruin communities, tear apart families and destroy lives."
While Khan does not have any power to decriminalise drugs, he said public figures must, “reduce the huge damage that illegal drugs cause to our communities.”