The Great British Sewing Bee Season 4

It's the grand final, and having made it through seven weeks of tough sewing challenges, the three finalists fight it out for the title of Britain's best amateur sewer; First, they must create three pieces of evening wear to impress the judges.

It's the semi-final with just four sewers left to battle it out to for a place in the final. All that stands in the way are three challenges designed by judges, Patrick Grant and Esme Young. This week they want to test the sewers' knowledge of complex patterns and pattern cutting. For the Pattern Challenge, the sewers are tasked with making an asymmetric yoked skirt inspired by modern Japanese pattern cutting.

It's the quarter-final, and the five remaining sewers sweat it out over activewear creating complex, hard-wearing garments from the most technical of fabrics. For the pattern challenge, Patrick Grant and Esme Young ask them to make a man's Lycra cycling top, which requires expert handling of a fabric that stretches in all directions and a complex zip insertion that tests their patience.

This week the sewing room is transported back to the 1960s as the six remaining sewers revive vintage garments, take on time-honoured techniques and wrestle with antique equipment in an attempt to show Patrick and Esme they deserve a place in the quarter-finals.

Patrick and Esme set the seven remaining sewers the challenge of tackling techniques and garment styles from other cultures and continents. First up, they face a fiendishly hard-to-follow pattern for a Chinese Qipao-style top. This complex garment has an asymmetrical neckline, fiddly zip insertion and is made in a fabric that frays - not a challenge for the faint-hearted.

Eight sewers return to the sewing room to take on delicate lingerie. The three demanding challenges require the sewers to work with the fiddliest of pattern pieces and the most delicate fabric. First they follow a pattern for a bra which proves testing for even the most dextrous of sewers, requiring precision engineering and some of the smallest pattern pieces ever seen in the sewing room.

Nine amateur sewers return, ready to show judges Patrick Grant and Esme Young that they can make beautiful clothes on a miniature scale. Claudia Winkleman sets the sewers three challenges, each designed to test different fabric handling skills on children's clothing.

Under the scrutiny of Savile Row's Patrick Grant and Central St Martin's Esme Young, ten fresh-faced home sewers face three challenges designed to test their skill and understanding of basic garment construction. First the sewers follow a pattern for a woman's top made up of four pieces.