The UK glamour model flew all the way to the United States in December 2010 for an appointment with top stylist Lea Journo, but when Journo wasn't available she was fobbed off on an apprentice.
The 33-year-old underwent a whopping 48 hours worth of treatment on her hair over the course of a week, paying $15,000 for hair extensions and a colour treatment which lightened her hair from brown back to her usual platinum blonde.
A source told the Daily Mail, "It looked fine once it had been blow dried but Katie said it felt uncomfortable and the extensions were tugging at the roots.
"When she got back to the UK she got a hairdresser to look at the extensions who said they had been applied unevenly. Her hair was very weak from the colouring. It was brittle and broke off easily, leaving different parts different lengths. At the front there were bits that were only a few centimetres long. The damage will take a long time to repair."
The salon offered Katie a 50 per cent refund, but later took back their offer after the star demanded a full refund plus compensation for the $60,000 she says she's spent trying to repair the damage.
And while Katie prepares to take legal action, the salon's employees don't seem too fazed about the bad publicity or the threat of a lawsuit.
When contacted by the Daily Mail, Alexandra Thomas, a colour technician at the salon, said, "None of us had any idea who she was when she started coming here. She's like Britain's answer to Pamela Anderson but not as pretty or successful, right?"
"There was a big bust-up recently and Katie was making a stink.
"I can't really talk about it but let's just say I don't think she'll be coming back. It doesn't bother us and to be honest it's a relief. We handle the biggest stars in Hollywood. She's a nobody."