Grand Designs

The story of one man's heroic attempt to fulfill his childhood dream and bring back from the ruins an incredible castle set in one of the most beautiful landscapes in Ireland. Kevin McCloud meets more people trying to build dream homes, beginning with Sean Simons, who bought the ruins of Cloontykilla Castle in the Irish county of Roscommon with a view to using them to create a spectacular mock-16th-century home. However, the outlandish plans - including jacuzzis in the battlements and water-spouting gargoyles - have Kevin worried the project could become a garish nightmare, and his scepticism increases when he realises Sean has not consulted an architect. Disaster seems to be looming as the contractors get frustrated and planning regulations are ignored, but somehow things begin to slowly take shape - until a national economic crisis plunges everything into chaos.

Kevin McCloud meets a pair of civil partnered university professors who have decided to build their first home from scratch. In addition to all the complications this usually entails, they have also enlisted the services of industrial designers who have developed a new computer-assisted method for cutting precision-engineered building blocks from scratch. However, though the technique may be clever, its creators have never created a building before - meaning everyone involved with the project is taking a giant leap into the unknown.

Mary Martin and Carl Turner want to build a home that resembles a giant stack of glass cubes in Brixton, south London. The couple are hoping the structure will become an instant landmark, while on the inside they are planning a Zen retreat. But to succeed, their finances must be pushed to their limit, so Carl takes on as many of the specialist jobs as he can to save money. Kevin McCloud follows their progress.

Kevin McCloud follows Lysette and Nigel Offley, who are knocking down an old Thames boathouse and constructing a cutting-edge home in its place. Taking inspiration from the river itself, they have designed a building of waves and curves with a huge glass porthole for a roof light. But problems begin almost from the start, as they can't find a contractor willing to build over the water, their architect leaves unexpectedly and the costs turn out much higher than expected. To make matters worse, the neighbours aren't happy about such a radical sight in their traditional community. As they begin to compromise, Kevin wonders if the couple's dreams will ever be realised.

Kevin McCloud marks the 100th episode with one of the programme's most ambitious projects to date. Leigh Osborne and Graham Voce want to convert and extend a landmark 150-year-old water tower in central London into a luxury home. Grade II-listed, derelict and with 6ft-thick walls, it's a huge challenge for the pair, who also plan to build two structures at the base - a lift shaft connected by a series of glass tunnels, and a modern living space. The result will be a four-bedroom property over nine floors, complete with a room at the top offering spectacular 360 degree views across the capital. The tower, which is located directly above London Underground's Northern Line, was originally built for Lambeth Workhouse in 1877 and became a Grade II listed building in 2008.

Kevin McCloud meets Audrey and Jeff, who dream of living in one of west London's most exclusive areas. However, the way they can afford it is to go underground. Their plan is to transform a listed Edwardian artist's studio - along with 5,000 sq ft of derelict basement - into a bespoke subterranean home, complete with supersize kitchen, mezzanine sitting room, four en-suite bedrooms, a gym, cinema, steam room and wine cellar. As if the task weren't tricky enough, they are doing it without proper architect's drawings and Audrey is project managing - and the difficulties begin almost from the start.

Kevin McCloud meets artists Indi and Rebecca, who are planning to build a modern, larch-clad home on the Isle of Skye, with a second hand-crafted building alongside to use as their studio, all on a tight budget of £150,000. They have been saving for years, but making it happen will mean taking on the savage weather, not to mention the sceptical locals - and as if that weren't enough, most of the work is being done by one man, local builder Donald.

Henning Stummel and his partner Alice Dawson attempt to convert an awkward,covered space, trapped between buildings in the crowded heart of north London into a contemporary family home and office for Henning's practice.

Kevin catches up with Lincoln Miles and his wife, artist Lisa Traxler, who had discovered an uninspiring 70s bungalow on the Isle of Wight on a prime piece of land surrounded by unspoilt ancient woodland and were going to convert it into their dream home.

Kevin catches up with Claire Farrow and Ian Hogarth who began a wild journey in 2010 to create d the ultimate fun family home, right in the heart of London, including a dance floor, dj booth and sauna.

Kevin catches up with Freddie Robins and Ben Coode-Adams who left their two bedroom London flat and took on the conversion of a huge Grade II listed timber framed barn in the Essex countryside.

Kevin saw a ground-breaking co-operative of ten families built their own homes on the edge of Brighton. They where known as 'The Hedgehogs' and were made up of former travellers and those living in insecure accommodation. Kevin catches up with the community over ten years on.

Kevin catches up with the story of a daring modernist home in the Andalucian hills in southern Spain.. Ten years ago Gil and Hillary Briffa decided to retire to southern Spain. Rejecting the coastal sprawl around Malaga they found a virgin plot of land up in the Andalucian hills for just £35,000. But instead of building a home like the traditional old fincas nearby, their architect son's design was a confrontational, modernist glass box, surrounded by boldly coloured connected rooms, hidden behind a giant citadel wall. Construction proved stressful. The couple put all their trust in a local Spanish builder who had never built a house like this before. The local residents didn't like it and the mayor tried to get it re-painted white. But if they could just finish the build, it promised to be the coolest retirement home Kevin McCloud has ever seen. Sadly, Gil died a few years ago, but now Kevin returns to meet with Hillary again and to see whether or not their building has settled into its landscape, whether it's still multi-coloured, and to find out just how life is for her as a British widow living up in the Andalucian hills.