For over 200 years, tailors have been crafting high-end bespoke suits on London's famous Savile Row. A custom-made two-piece suit can cost £6,000. And while a tailor's tools are simple, the skills needed to turn a paper pattern into a pressed suit takes years to master. We followed Kathryn Sargent, the first female Master Tailor on Savile Row, to find out how she crafts a bespoke suit — and to learn what makes Savile Row suits so expensive.