The Great British Sewing Bee S09E04 - Episode 4

Taking on the fast fashion industry, the second most polluting industry in the world, Sara Pascoe welcomes back Reduce Reuse Recycle week. First, the sewers attempt a zero-waste pattern for a pair of trousers, which involves complex mathematical skills to work out how to create the pattern pieces without leaving a scrap of waste fabric.

In the Transformation Challenge, the sewers use up a mountain of waste tote bags to create a garment. They can combine several bags to transform them in just 90 minutes, making imaginative use of the different prints and straps.

Finally, the sewers have been asked to source second-hand crochet blankets to create a made-to-measure outfit. They need to ensure that while chopping up their blankets, they don't unravel before they are sewn into outfits.