THEY look the part. Big eyes and wet nose, adorable fluffy puppies carefully posed with a favourite toy or snuggled in a clean blanket and advertised for sale an online marketplace site.

For families desperate to find a four-legged companion, the prospect of taking one home without asking too many questions is tempting. But behind the pretty images the reality, of course, is far from pleasant. For the animals crammed into tiny cages, stinking from the faeces and urine that clings to their fur and ridden with disease, bitches weak from almost permanent pregnancy, cowering in the dark in fear of another beating, it is horrific.

A lingering death comes to some. Perhaps they are among the luckier ones. For quite often the only thing thriving at illegal underground puppy farms, is the unscrupulous breeders’ bank balances.

Puppy farms produce one in three dogs bought in the UK. Some are run by licensed breeders who tend to stick to minimum standards.

Others are run illegally, a money-spinning machine with roots in organised crime and unsuspecting families who simply crave a pet to love and care for.

The online puppy trade is estimated to rake in £13 million every year. With regulated pet shops banned from trading in puppies and the ease of the internet age, for most would-be dog owners the only way to track down a pet is online.

According to animal charity OneKind, the mark up is such that a French bulldog – currently one of the most popular breeds – can sell for £387 in the Czech Republic and £1,586 if trafficked to the UK. A dachshund bought for £96 in Romania can fetch more than £1,000 in the UK.

In 2016, BBC’s Panorama went undercover to film conditions at Irish puppy farms. The shocking footage showed dozens of dogs packed into dilapidated cages, giving birth in freezing boxes with little to no ventilation.

Once here, smooth talking fraudsters can easily persuade someone desperate for a puppy to part with their cash. Some are caught. Robert Brownlie of Newmains, was banned for life from owning animals in November 2016, after a Scottish SPCA probe into puppy trafficking. Then in May last year it emerged that two cousins killed in a speedboat accident, Sandy Hamilton, 35, and Kevin McKinlay, 46, had worked closely with Brownlie.

They were said to have been involved in trafficking thousands of dogs from Ireland for sale in Scotland, buying them for €50 each to sell for up to £1,000.

Even then, puppies’ face a difficult future. Experts say horrendous conditions can severely impact the mental health of dogs, potentially leaving them hostile and aggressive. Without proper vaccinations, disease takes hold and many quickly succumb.

There are 97 licensed breeders in Scotland, but it has been claimed that even some legal breeders have kept dogs in cramped, filthy cages. Now the Scottish SPCA has called for strong deterrents in a bid to end the puppy trade. Whether a nation of dog lovers can find the strength to log off and avoid the unscrupulous online dealers, however, remains to be seen.