Dom and Melinda are in Balham to help a pair of newlyweds who had plans to extend their ground floor flat. Following the death of her mother, Sarah and her partner Stuart decided to use the inheritance money to extend their home in south London. They paid their builders £85,000 of a £95,000 contract, but were left with an unfinished shell and severe structural problems. Due to shoddy building work, the entire three-storey block of flats in which the couple live is in danger of collapse.

The state of the building is so bad that before Dom and Melinda are even allowed access to the building, a structural engineer insists that emergency props are installed to safely support the walls.

Melinda and her team plan to fix the botched work and complete the extension. However, these efforts are thwarted at every turn, as at each stage of the repairs yet more problems are uncovered. Will the team be able to overcome these obstacles to give the couple the apartment they deserve?

Meanwhile Dom's investigation reveals that Stuart and Sarah are far from the only victims of this bunch of cowboys. He discovers that the company are making some misleading claims on their website and, as Dom tries to confront the builder in question, he discovers that he is a very difficult man to pin down.

After living in their house for 17 years, a couple decide to invest in an extension for the sake of their adult sons. They thought that by hiring a female builder to undertake the work, they would get someone that they could trust. However, after spending £36,000 they were left with a devastated wreck with no electricity, water or heating.

Dom and Melinda go to Bradford to help a couple who hoped to build an extension which would provide a bedroom to each of their children. Ayaz and Shazia spent £30,000 with a father and son building team to do the job. Instead they were left with a whole host of problems – including an extension without a roof, exposed live electrics and a number of inadequate steel beams. The parents and two daughters are forced to camp in their lounge, while their two sons are stuck sharing a freezing, damp-ridden bedroom.

It's Dominic's mission to find out how a supposedly experienced builder – with three decades of building under his belt – could have made so many basic errors. It's not long before he uncovers a string of unhappy customers, a suspicious lack of paperwork, and a wayward son whose work - and behaviour - on site is a major cause for concern.

Meanwhile, Melinda's got her hands full with the massive building project. Hampered by the problems she uncovers, Melinda appeals to the local community to help the family. She's inundated with offers – including one from the local rugby league team.

When Dom finally catches up with the builder, he finds a man in denial about both his building work and the actions of his son.

Dom and Melinda investigate the work of a septuagenarian builder who has over half a century of experience in the building trade.

Lawrence and Helen live in Berkshire with their three children. Wanting to give their girls a bedroom each, the couple remortgaged their property in order to pay for a two-storey extension on the rear of their house. Despite having paid £38,000 of a £46,500 quote, the family were left with an unfinished shell.

Worse still, in the process of putting up the extension, the builder also managed to destablise the existing roof and carried out substandard underpinning work to the existing foundation causing cracks to appear in the rear area of the property.

Melinda and her team try to fix the myriad problems with the building work. Meanwhile, Dom gets on the case of the builder responsible and discovers that his bad building habits have been going on for years. Putting the rogue under surveillance, can Dom catch him in the act?

Simon and Diane bought a detached house in the affluent town of Guildford with a view to extending it so their adult children could live with them. The builder they hired took £54,000 of a £60,000 quote, but left much of the work incomplete. Dom decides to organise a surprise party for the rogue and invites as many of his victims as possible.

When Neil and Davina needed an extension to their two-bedroom semi in West Sussex, and their architect recommended a local builder, they thought he would have no excuse not to show up. However, the contractor frequently failed to show. Seven months later, with £25,000 invested, the extension is still half-finished and building control found 15 faults with the work.

Melinda is more than a little upset by the situation, and everywhere she turns she uncovers more wonky workmanship. She vows to get things shipshape, and sort out the shoddy shambles.

Meanwhile, Dom starts sleuthing around, discovering that the builder has left quite a trail of destruction around the neighbourhood. When he finds out that the builder has left town, Dom pulls out all the stops to track him down.

In south London Mel and Dom meet the Marrs, who have saved up to afford an extension to their kitchen. After paying a building company £23,000 the contractors have disappeared leaving just foundations, a floor and two walls.

While Dom tracks down the culprits, Melinda has her work cut out finding the structural steel needed to rebuild the extension.

The dynamic duo are in Dorset to revisit one of the worst cases of shoddy building work either had ever seen at the time. When grandmother Karen was struck down by cancer, she needed her own quiet bedroom to recuperate. A builder the family had known for four years quoted for an attic conversion, but after four months he walked off the job.

The dynamic duo catch up with two of their favourite stories to see what has happened since. They focus on cases in Bolton and Sheffield.