The retail guru heads to the Suffolk seaside town of Lowestoft to take on her biggest challenge yet. She's working with Godfreys, a family-run department store that customers are deserting, resulting in a dire financial situation. Owner Jim has shared management duties between his stepchildren Laura and David, but with a massive overdraft, the store's future is in doubt. Determined to turn the staff into product-knowledge experts, Mary organises a trip to Spitalfields Market and devises a customer-service test in an attempt to give the team the confidence they need.

• Mary Portas