The semi-finalists transform dressing rooms at OVO Arena Wembley, and pop princess Sophie Ellis-Bextor joins Michelle to decide who will go through to the final.

The six remaining designers are set their next challenge. They are off to the cathedral city of Salisbury to transform three very different shops.

The five remaining designers come up with clever hacks to show potential tenants how to turn Sheffield rental apartments into homely spaces - without losing their deposit.

The designers pair up and hit East Grinstead high street to transform two Grade II listed shops. They need to transform the spaces to impress Mary queen of shops.

The new cohort of interior designers tackle their first challenge, demonstrating their signature style on YHA bunk rooms in the Lake District.

Alan Carr hosts a new series of the interior design challenge, in which 10 aspiring designers compete to redesign Oxfordshire show home. Michelle Ogundehin assesses their efforts, and is joined in the first episode by guest judge Laurence Llewelyn-Bowen.

The designers hit the high street, doing up shops in Rye. Working in teams, they transform an Indian paper shop and a women’s boutique before being critiqued by Mary Portas.

Head judge Michelle Ogundehin challenges the contenders to transform upmarket rental flats in Manchester.

The three semi-finalists are challenged to upgrade luxury holiday lodges in the Cotswolds. They must make their mark with some design flair while keeping in the mind the target market.

The nine designers demonstrate sustainable design by transforming shipping containers into offices in Bristol for start-ups using recycled and repurposed materials.

The designers create a home from home for dogs at Battersea. Sue Perkins helps Michelle judge these transition rooms along with a couple of Pomeranian rescues.

The finalists transform holiday cottages in the whimsical and colourful village of Portmeirion before one of them wins Interior Design Masters and a contract with John Lewis.

The designers are let loose on exclusive hospitality boxes at Ascot Racecourse, with each creating their own personal interpretation of high-end sophistication and luxury.

The designers are sent to Wotton House in Surrey, a Grade II listed grand hotel. There they must each update a bedroom in their signature style, incorporating a 'British eccentric' twist.

In teams of two, the final four designers renovate two cafes in the seaside town of Margate.

Ten budding interior designers are challenged to transform luxury apartments in London’s Elephant and Castle. Hosted by Alan Carr.

Romance is in the air as the quarter-final challenge involves wedding accommodation on the banks of Rutland Water in the East Midlands.

A new batch of interior designers show off their signature style by heading to a former Norfolk convent, turning nuns’ cells into bijoux B&B bedrooms before one wins Stand Out Space.

The eight remaining interior designers take part in a challenge to transform shop interiors. Presented by Fearne Cotton, with judge Michelle Ogundehin and guest judge Mary Portas.

The six remaining interior designers take part in a commercial design challenge to transform university halls of residence. The guest judge is Sophie Robinson.

Working solo, the five remaining designers each transform a shepherd's hut on a glamping site in north Wales. The spaces are small, so practicality is key.

Having survived seven tough challenges, the two finalists must now redesign two trendy bars in London's Soho.

The eight designers pair up to transform luxury retirement apartments in Portsmouth, using their home staging skills to attract baby boomers into buying their forever home.

The nine remaining interior designers take part in a commercial design challenge to transform London offices. Presented by Alan Carr with judge Michelle Ogundehin.

The three remaining designers return to Brighton to discover their penultimate challenge – a hair salon makeover in Bristol.