The activist follows the trail of this business all over Europe. She talks to animal sanctuaries, police, vets and duped buyers. "I’ve been physically attacked and of course, you receive threats,” says Birgitt Thiesmann, "that’s just simply part of the job.” For more than 20 years, Birgitt worked as a reporter for the German youth magazine "Bravo”. After writing a reportage on the illegal puppy trade in Europe, she joined "Four Paws". Since then, she’s been part of the fight against criminal traders. Experts estimate they earn around one billion Euros selling puppies in Europe. This makes the illegal puppy trade just as lucrative as the criminal trade in drugs, weapons or women. "The puppies are usually terminally ill. They’re not vaccinated or wormed and many of them die straight after they’ve been sold,” says Birgitt, who maintains contact with many duped and shocked buyers. She regularly follows the tracks left by criminal puppy traders across the continent. In Prague, she meets someone who quit the business. The woman used to be what’s known as a "multiplier” - animal activists describe these outfits as "puppy mills” and never as "breeding”. Birgitt’s hoping to glean some new insider information and isn’t disappointed: she hears about another, so far undiscovered "multiplier station” not far from Prague. "This has nothing at all to do with responsible breeding,” says Birgitt. She sees the consequences all over Europe: overcrowded animal shelters in Germany and puppies displaying challenging behavior in the kennels of Belgian dog handlers. Nevertheless: Birgitt and her fellow campaigners are making a difference, albeit on a small scale. Posing as a potential buyer, she tips off vets and the police and catches puppy traders red-handed, confiscating dogs that have evidently been smuggled into Germany.