Dom and Melinda are in Milton Keynes, helping out a family who were left with nowhere to wash themselves but the kitchen sink. In 2011, Kate Snow, husband Mike and their two sons Henry, 20, and Richard, 17, wanted to adapt their three-bedroom home. Kate suffers from chronic degenerative spinal arthritis, and a ground-floor office for their home business and a disabled access wetroom were vital. They pulled together their life savings and paid a local building company £34,000 to convert their garage, existing bathroom and downstairs toilet, with some additional work to the driveway and garden. It should have been a simple six-week job... Six months later, the builder walked off with their money, leaving the family with an unfinished, uninsulated, unsafe mess. It looks like a straightforward job for Melinda and her team, until they discover that nothing is as simple as it seems. Meanwhile, Dom uncovers a trail of debts and broken promises left by the builder, stretching across the Midlands and beyond. For once it looks like the cowboy is one step ahead, as he tries to pay off his victims to stop them talking...

• Melinda Messenger
• Dominic Littlewood