Willie, who is 48 and sleeps on the streets of Dundee, has lived a life of misery and stubborn addiction after medics were forced to remove his leg when an evening of hunting for his latest fix went catastrophically wrong.

The amputee is unclear whether he lost his leg because of a dirty needle or whether the drugs were packed with unknown, potent substances.

The chaos of the evening that changed his life is a blur and something of a mystery.

On the frontline of Scotland's drugs death emergency, Willie says there's "no support" as a new wave of crack cocaine washes over his hometown.

Dundee - a city home to fewer than 150,000 people - has been the notorious epicentre of Europe's overdose crisis for years. Many of Willie's friends have been killed.

There has been a sharp and sustained rise in drug deaths across Scotland since 2013.

Despite a slight dip in 2021, a record number of lives have been lost in the last decade with former First Minister Nicola Sturgeon previously admitting her government "took our eye off the ball".

Drug deaths predicted to fall

Experts have told Sky News the latest drug death figures, set to be released on Tuesday, are likely to show the loss of life among Scots is finally decreasing.

One leading figure claims there could be a substantial drop in the most recent 12-month period - but the havoc is far from over on the streets of Dundee.

Professor Catriona Matheson, an expert in substance misuse from Stirling University, said: "All the indications I have seen show the figures for 2022 will be reduced. Not just a little bit.

"It means some of the initiatives that have been put in place are starting to have an effect.

"But, we cannot say we are on a downward trajectory because there is an illicit market with new synthetic opioids which are very cheap, potent and we are starting to see those coming through."

Acid attacks and £10 valium

Staggering down the street is one mum who is gripped by dangerous cravings. She tells a frightening tale of acid being poured over her legs amid a struggle with a drug debt linked to an underworld figure.

She is in agony as the open wounds on her limbs ooze bodily fluids.

Sky News went inside the nearby Lochee high-rise estate, where locals told of a dangerous scene where crime is rife and drugs are deadly.

One father, Barry Richie, describes the relentless loop of having to dodge people suffering overdoses in the common areas and stairwells.

He said: "I can't bring my kids here on the weekend."

Addicts on the scheme say access to illegal substances is easier than ever. One says he can get a packet of 25 valium pills for £10 within "seconds" by making a quick phone call.

Another user said: "The place is flooded with crack. It has always been bad but this year it is 100 times worse".

The presence of Sky News became a problem when one dealer approached the cameras with a thinly veiled threat suggesting he had his throat "slit" recently and the police don't scare those involved in the drugs trade.

"You are being watched right now," he warned.

A short time later the situation was at risk of being hostile and filming was abandoned.

Street benzos, blues, diazepam and valium

The types of substances are an evolving picture.

There were 918 deaths involving benzodiazepines in 2021, nearly five times as many as 2015.

The prescription drugs, which mostly come via the black market, are commonly known as street benzos, blues, diazepam and valium.

Street performer Jesse Jones says pills these days would "blow your mind" compared to the strength of heroin.

The 53-year-old, who plays the bongos in Dundee's main shopping area, says he can get a handful of 25 valium tablets within minutes for less than the price of a bottle of vodka.

He said: "There was one time I was at my girlfriend's and I had taken four and I instantly recognised why people are dying. I was scared. If I had taken another 15, I would not be here.

"Some people are crazy on it. It does bring the worst out in people. This is like a different planet. It is light years apart compared to heroin."

Drugs deaths are now recognised as one of the biggest contributors to Scotland's falling life expectancy. Some data indicators suggest overdoses among Scots are higher than even in the United States.

The rate of death compared with the available figures from European neighbours reveals the extent of Scotland's problems.

Why is Scotland unique?

Experts say poverty and lack of opportunities are the key drivers.

People in the most deprived areas of Scotland are more than 15 times as likely to die from drugs compared to those in an affluent area, according to the National Records of Scotland.

Kirsten Horsburgh, who has worked in drug treatment services for more than a decade, is chief executive of the Scottish Drugs Forum. The charity is a leading voice on the crisis.

She said: "A lot of the same problems exist in England and in other areas in terms of poverty, deprivation and trauma. But the issues are more concentrated in Scotland.

"One of the drivers for drug-related deaths is the lack of people being in the treatment that would potentially save their lives. We have less than 40% of people accessing that treatment. In England, they do have more people accessing treatment.

"There has definitely been progress in the way our treatment services are delivered and improvement with standards to get people accessing more timely treatment.

"We know that there is likely to be a slight reduction in the numbers of deaths that we will see [in Tuesday's latest figures]. This is positive but it is still not a sign of success when we will still have well over 1,000 people having died.

Drug laws are currently reserved to Westminster but the Scottish government has control of health and social policies around drug consumption.

Ministers in Edinburgh have ploughed in £250m into the country's addiction services but key targets have been missed.

Data suggest almost 60% of services have not given addicts the option to start treatment the same day they turned up for help, despite that being the expected standard.

It has resulted in charities taking matters into their own hands.

As figures show the number of women dying from drugs is on the rise, Sky News was given special access inside a unit for homeless women who are addicted to drugs.

The facility, run by the Simon Community Scotland, has changed its approach to move away from a "no tolerance" approach to drug use.

Previously the shelter's residents risked losing their room if they were caught taking substances within the building but amid the growing national emergency, the charity shifted its stance.

Clean needles and safe injecting equipment is now provided in a special harm reduction room alongside naloxone which is a medication to reverse opioid overdose.

Hannah Boyle, from the charity, said the results have been game-changing.

She said: "In 2020 we tragically lost 17 people in our residential services and in 2021 we lost one person. That is a dramatic shift and decrease in numbers.

"We have been able to save lives as much as we can and really change our approach to make sure people have what they need when they take substances and they have a quality of life."

Is residential rehab the answer?

The Scottish government's strategy to get a grip on the ongoing emergency is funding more residential rehabilitation facilities.

Ministers aim to increase bed capacity to 650 and ensure there are at least 1,000 publicly funded placements.

Nestled in the rural fields of Fyvie, Aberdeenshire is the Sunnybrae rehab unit.

It is a Christian programme where addicts enrol for 12 months on a strict regime of Bible-based learning and counselling to rebuild their lives.

Mobile phones are banned and residents are weaned off all substances - including tobacco - in as little as two weeks.

Leaders said more than 450 people have taken part in the abstinence model over the past 20 years.

None of the current participants were directly referred by the NHS, they are all "self-referrals" who complete a Sunnybrae application process.

The unit has received more than £700,000 of taxpayer funds.

Paul Beaton, course supervisor, also revealed their internal data suggests more than half of residents either relapse back into their old life or are unaccounted for.

He said: "People come to us with pretty much every area of their lives broken, physically, mentally, emotionally, financially.

"We help them get to the root causes to give them healing, peace and freedom from the issues that drive them to substances in the first place.

"We really focus on them having a strong 'move on' plan for the end. We really work hard to set them up for the win. Our success rate, the number of people going on to lead clean, free, sober lives is 45%. Which is great."

Some experts in the drug recovery sector believe other rehab models are more effective.

Kirsten Horsburgh, from the Scottish Drugs Forum, said: "We are supportive of residential rehab being available when they want it. Pushing people towards an abstinence situation is not helpful because it can increase people's risk. Abstinence should be available but it's not a superior approach.

"Having services available for people when they want to stop using drugs is important but it's not an emergency response and that is often missing from these conversations."

The latest official figures revealing the most up-to-date drugs death toll in Scotland will be revealed on Tuesday.