The Great Interior Design Challenge is back for a third series, with 16 talented amateur designers battling it out for the title across 15 episodes, plus a special one-off programme featuring secrets and tips from our designers, judges and guest experts. Each knockout heat takes place over three episodes, where a group of four designers are whittled down to just one who will go through to the quarter final. They'll compete in a series of challenges, taking on similar rooms in neighbouring properties with three days, £1000 and the help of a small team. They'll also be tested on their client presentation skills and creativity, being surprised with an item to upcycle each time. The designer who fails to interpret the homeowners' briefs and impress the judges will be the one chosen to leave the competition. In the first round of the first heat, the group of amateurs taking on the design challenge are youth worker Jane, actress Sharon, doggie day carer Holly and ex-textiles salesman Frankie. They must transform a bedroom each in a modernist former leisure centre in South London – one of presenter, and architectural historian, Tom Dyckhoff's favourite buildings in the UK. Jane has a nervous wait using concrete to make elements of her modern, Scandi scheme – and is even more anxious to find out if her exacting client likes her scheme. Sharon is being bold with colour to answer a Bloomsbury inspired brief – but she may have gone too far for her homeowner. Holly gives herself way too much to do, transform a kid's bedroom with loads of craft projects – including creating a 'selfie booth' for her young client. While Frankie faces disaster after deciding to upholster huge parts of his Japanese inspired design – including the wardrobe. Can he finish it to his own high standards?